Simone Biles said she had put her "mental health first" after missing out on adding a fifth Olympic gold medal to her collection following an early withdrawal from the women’s team final.

The 24-year-old gymnastics icon revealed she was “dealing with things internally” after a disappointing performance on the vault.

Biles posted the lowest score of the first rotation on Tuesday as she landed awkwardly after failing to execute an Amanar, while only completing a Yurchenko 1.5 twist.

After she subsequently withdrew, Team USA had to settle for a silver medal behind the Russian Olympic Committee while Great Britain completed the podium.

Biles admitted that she was "fighting demons", explaining: "I just don't trust myself as much as I used to. I don't know if it's age. I'm a little bit more nervous when I do gymnastics. I feel like I'm also not having as much fun."

She added: "I say, 'put mental health first'. Because if you don't, you won't enjoy sport and won't succeed as much as you want to.

"So it's okay sometimes to sit out the big competitions to focus on yourself, because it shows how strong a competitor and person that you really are, rather than just battling through it."

OSAKA STUNNED

The big names continue to tumble in the women’s singles tennis event, with second seed Naomi Osaka defeated in straight sets.

The home favourite, who lit the Olympic cauldron on Friday, was denied a place in the quarter-finals after being ousted 6-1 6-4 by world number 42 Marketa Vondrousova.

This event marked Osaka’s first competitive tennis in two months since her early withdrawal from the French Open at the end of May, citing mental health issues.

The world number two is the latest of the big names to fall at the Tokyo Games, with top seed Ash Barty and third seed Aryna Sabalenka also suffering early exits.

"Of course, it's one of the biggest wins of my career," Vondrousova said. "Naomi is a great player, so I knew it would be a tough match. 

“I'm very happy with my play. I played amazingly in the first set, and then the second set was really tough. I'm just happy to be through."

ARGENTINA RECOVER TO SEE OFF SPRINGBOKS

Argentina recovered from a dreadful start to beat South Africa and book their place in the rugby seven semi-finals.

Trailing 7-0 after just under two minutes, the Pumas were then reduced to six men when Gaston Revol - who was reduced to tears - was shown a straight red card.

Nevertheless, they demonstrated tremendous resilience and character before eventually running out 19-14 winners.

Argentina will play Fiji in the last four after the reigning Olympic champions swept Australia aside 19-0.

Great Britain stormed back from 21-0 down to beat the USA, scoring four tries to secure a dramatic 26-21 victory.

Team GB will play New Zealand, who eased to a 21-10 success over Canada.

Barbadian swimmer Alex Sobers has announced that he is taking a break from the sport after the Olympic Games Tokyo 2020.

Sobers competed in two events in Tokyo. The two-time Olympian first took part in the Men’s 400m Freestyle, where he finished 7th in heat 2, in a time of 3:59:14. His other event was the 200m Freestyle where came 6th in heat 2, but in the process set a new national record of 1:48:09.  The time beat his previous record of 1:48:35. He, however, did not advance to the semifinals of either event

Even before hitting the pool on Saturday, however, Sobers was the centre of attention for the Barbadian public.  Many were left irate by the prediction of veteran journalist Mike King who cast doubt on the athlete’s prospects of advancing at the Games. The article was met with fierce backlash from angry Bajans who voiced their opinions on social media, they accused King of undermining the efforts of the 22-year-old. It is unsure whether the controversy had anything to do with his decision.

Another Barbadian journalist, Anmar Goodridge-Boyce, quoted Sobers via his Twitter handle, as saying, “I am just going to take a break and if I miss the sport, I will come back. If I don’t, I feel like I’ve definitely achieved everything that I set out to do”.

 Sobers first competed at the Olympic Games at Rio 2016 in the men’s 400 metre freestyle. He swam a time of 3:59:97. He did not advance to the semifinal.

Japanese superstar Naomi Osaka crashed out of the Tokyo Olympics tennis with a 6-1 6-4 defeat to Czech world number 42 Marketa Vondrousova.

Osaka, who lit the flame at Friday's opening ceremony, had won her opening two matches but bowed out in straight sets, with Vondrousova reaching the quarter-finals.

In the first set, Vondrousova dominated on her first serve and broke three times, before the Japanese hit back with an early break in the second. But the Czech fought back to win, with Osaka finishing with 32 unforced errors to just 10 by her opponent.

"Of course it's one of the biggest wins of my career," Vondrousova said. "Naomi is a great player, she has so many grand slams, so I knew it would be a tough match. I'm very happy with my play. I played amazingly in the first set, and then the second set was really tough. I'm just happy to be through."

World number two Osaka joins top seed and Wimbledon champion Ash Barty in being eliminated early at the Tokyo Games.

In the men's singles second round, fourth-ranked Greek Stefanos Tsitsipas eased past American Francis Tiafoe 6-3 6-4, avenging a shock Wimbledon defeat.

DUFFY DELIGHT

Flora Duffy won Bermuda's first-ever Olympic gold medal with victory in the women's triathlon on Tuesday at Odaiba Marine Park.

The four-time Olympian failed to finish in Beijing, came 45th in London and improved to eighth in Rio de Janeiro.

Duffy took the Tokyo title in a time of one hour, 55 minutes and 36 seconds, finishing more than a minute ahead of Britain's Georgia Taylor-Brown who took silver, with USA's Katie Zaferes claiming bronze.

“It's always been my dream to race at the Olympics and be a professional athlete with the goal of being an Olympic champion," Duffy said.

"That's not the easiest thing to do regardless of where you're from. Bermuda is a small country, but it's really passionate about its sport.

“I'm so grateful that I could achieve a personal dream here of winning an Olympic medal, but this is bigger than me, this is going to inspire the youth of Bermuda and everyone back home that competing on the world stage from a small island is really possible."

The 33-year-old broke clear in a group of seven early in the bike stage, before dominating the 10km run.

Bermuda, which has a population of just over 70,000, had only claimed one medal previously in Olympic history, a bronze in 1976.

MCKEOWN BREAKS OLYMPIC RECORD

Australia secured a second gold medal in the pool as Kaylee McKeown broke the Olympic record in the women's 100m backstroke.

McKeown won in 57.47, finishing ahead of Canada's Kylie Masse by 0.25 seconds, with USA's Regan Smith taking bronze. Masse had led at the turn.

In the men's 100m backstroke, Russian Olympic Committee claimed a one-two finish as Evgeny Rylov edged out countryman Kliment Kolesnikov, who holds the 50m world record. Ryan Murphy, who is the world record holder across 100m, claimed bronze.

Great Britain's Tom Dean won the men's 200m freestyle by 0.04, marginally ahead of compatriot Duncan Scott, with Brazil's Fernando Scheffer coming in third. The result meant two British male swimmers stood on the same Olympic podium for the first time since 1908.

World record holder Lilly King finished third as US teenager Lydia Jacoby triumphed in the women's 50m breaststroke. South Africa's Tatjana Schoenmaker claimed silver.

CHINESE PAIR ON TARGET

China claimed another gold medal in the final of the 10m air pistol mixed team at the Asaka Shooting Range.

China's Ranxin Jiang and Wei Pang won 16-14 over Russian Olympic Committee pair Vitalina Batsarashkina and Artem Chernousov.

Ukraine duo Olena Kostevych and Oleh Omelchuk won the bronze by beating Serbia.

The 10m air rifle mixed team bronze and gold medal matches were taking place later on Tuesday.

AUSSIES SINGING IN MEN'S HOCKEY

World number two side Australia knocked off reigning Olympic gold medallists Argentina 5-2 in the men's hockey group stage.

Australia claimed their third consecutive victory and top Group A, this time being aided by two goals from Blake Govers.

The Kookaburras have only won one Olympic gold despite often being a dominant side in men's hockey and are one of the favourites to triumph in Tokyo.

Japan and New Zealand, who both previously lost to Australia, drew 2-2 in the other Group A game.

In Group B, world number four India won 3-0 over Spain, while fifth-ranked Germany beat Great Britain 5-1.

Another great day in the pool saw Team GB and the Russian Olympic Committee secure one-twos, while teenager Lydia Jacoby earned a surprise triumph and Kaylee McKeown brought home another swimming gold for Australia.

There was also a further look at Ariarne Titmus and Katie Ledecky at the Tokyo Aquatics Centre, with the pair securing their passage to the final of the women's 200 metres freestyle.

Here is a round-up of Tuesday's goings-on in swimming at the Olympics.

MORE AUSSIE SUCCESS AS MCKEOWN SETS NEW OLYMPIC MARK

Just a day on from Titmus' thrilling win over Ledecky in the 400m freestyle, Australia had more reason to celebrate in the pool on Tuesday as McKeown won the 100m backstroke, becoming the first Australian woman to triumph in the event.

Her time of 57.47 seconds established a new Olympic record, the fourth time this week in the event a new benchmark has been set, and was only 0.02 seconds off her own world-record time.

Kylie Masse had led at the 50m mark and the Canadian held off the challenge of Team USA's Regan Smith to take silver.

DEAN PIPS SCOTT AS GB GO ONE-TWO

A thriller in the men's 200m freestyle saw Tom Dean pip Duncan Scott to gold as two British male swimmers stood on the same Olympic podium for the first time since 1908.

Scott was fastest in Monday's semi-finals and a blistering finish put him right in contention, but it was Dean, having made a superb opening, who just touched home first by four hundredths of a second.

"I knew it was going to be a dog fight," Dean, whose time of 1:44.22 is a new British record, told BBC Sport.

"I didn't know how people were going to swim it. It was just race to race."

TEENAGE KICKS AS JACOBY UPSETS THE ODDS

The shock of the session came in the women's 100m backstroke where American world-record holder Lilly King and Olympic benchmark setter Tatjana Schoenmaker of South Africa were favourites for gold.

There was an American winner but it was not King, the honour instead going to 17-year-old Jacoby, who became only the sixth swimmer to break 1:05.

The teenager broke free in the final 20m and defending champion King was proud of her younger team-mate's phenomenal achievement.

"We love to keep that gold in the USA family so this kid just had the swim of her life and I'm so proud to be her team-mate. I'm proud to get bronze for my country," King said.

RUSSIAN DUO BEAT MURPHY IN 100 BACK

Defending champion and world-record holder Ryan Murphy had to settle for bronze in a lightning 100m men's backstroke final, which saw the Russian Olympic Committee secure a one-two.

Evgeny Rylov (51.98), the 200m back world champion, edged compatriot Kliment Kolesnikov (52.00) in a tight finish as the USA did not win either gold or silver in this race for the first time since 1980 – when they boycotted the Games.

TITMUS AND LEDECKY TO BATTLE AGAIN?

If Monday's 400m clash was anything to go by then we could be in for another treat at the pool on Wednesday. Titmus qualified fastest in the women's 200m freestyle, with Ledecky winning her heat and going through third quickest overall.

Kristof Milak, who owns the world record, swam fastest in the men's semi-finals for the men's 200m butterfly, while Kate Douglass was quickest in the semis for the women's 200m individual medley.

Adam Peaty is convinced the morning starts for swimming finals are contributing to uncertainty in the pool at Tokyo 2020 and hopes defending his Olympic title sparks a gold rush for TeamGB.

Organisers have scheduled swimming finals to take place earlier in the day in the Japanese capital, with the heats being held in the evening.

There have been some notable shocks already, with home favourite Daiya Seto failing to make it out of the heats in the men's 400 metres individual medley, while Tunisian teenager Ahmed Hafnaoui earned an upset win from lane eight in the final of the 400m freestyle.

Coming into the Games, there was talk of whether Peaty could beat his own astonishing world record of 56.88 seconds in the 100m breaststroke.

While unable to do so, Peaty still dominated the competition, winning Monday's final in a time of 57.13, the fifth fastest of all time. 

For 26-year-old Peaty, ensuring he got the job done was the all-encompassing motivator given the way others have struggled.

"To be honest, I've never known swimming like this before," Peaty told a roundtable of journalists after winning gold in Tokyo.

"Normally you've got a solid one-two or maybe three if you can call it. You can't really predict it, in the 400 free there was a Tunisian guy [Hafnaoui] who won it in lane eight. 

"You can't predict that, so I think it is something to do with the morning finals and it's how the athletes adapt to that. I think it was the same in Beijing. 

"Sport is changing and the way we adapt, we train, and focus on mind and body and how we have to balance those. 

"I mean I'm fed up of talking about COVID but it's given us a chance to sort of really think differently about that and there's been a few breakout performances from COVID. 

"Would the medal table look very different last year? We don't know and we'll never know, but yeah it's definitely different."

Peaty, who became a father within the last year, was very open about the pressures he has been through in recent times.

Asked about the contributing factors to that pressure, Peaty said: "I mean put it simply we've seen over these two days, maybe three days, which is a lot of unexpected performances.

"A lot of people who should be going in here defending and winning medals are kicked out, especially in swimming we had Daiya Seto who is Japanese in the 400IM, he didn't make the final. 

"These Games are very, very different, and that's how we talk about pressure now. Mel [Marshall – Peaty's coach] said last night and a few of the other coaches have too, it's not about the times here, no one cares about the times, it's about the race, who wants it more in that last 20 metres. 

"It made me think completely differently, that every single championships I chase times because that's kind of validation for my training, I've trained really well this season.

"But it doesn't matter here, it's about the race, getting on that wall first, but also taking in every single trip and every single moment I can for these Olympics and hopefully inspiring as many people as I can while doing it."

It was five years ago in Rio where Peaty won TeamGB's first gold of the Games, acting as the springboard for a hugely successful Olympics whereby Great Britain won 27 golds and finished second in the medal table.

His success in Tokyo was also TeamGB's first and was quickly followed by triumphs for Tom Daley and Matty Lee in the men's 10m synchronised diving, while Tom Pidcock won the men's cross-country in mountain biking.

"I literally caught it, I caught Tom and Matt on the last dive and it was anti-climactic for me because I don't know how many rounds there are in diving – and I saw them dive, and I saw the Chinese dive because I think they were the last to go and I saw Tom celebrating and I thought 'oh my God they must have won' and yeah that's the beauty," added Peaty, who became the first British swimmer to defend an Olympic title.

"I said that it could be a catalyst, not that it's down to me, those athletes are amazing. But it shows you when we come together as a team and show that kind of community spirit anything is possible. 

"We've got three golds, who knows what the rest is going to bring, what the rest of the week is going to bring. 

"I know Duncan Scott is up in the morning on the 200 free and he's a very strong candidate for gold there. Hopefully we've got it rolling now and we'll see the gold rush, eh?"

The Tokyo Olympics are now in full swing and there are another 22 gold medal events to come on an action-packed Tuesday at the Games.

Plenty of focus will be on the Tokyo Aquatics Centre once again, where four medals are on the line, while the women's triathlon will also take centre stage.

Simone Biles, Naomi Osaka and Katie Ledecky are just some of the superstar names that will be in action on the fourth full day of the 2020 Games.

Stats Perform picks out of some of the standout action to look out for.

CAN BILES PUT BLUNDERS BEHIND HER?

Biles struggled to find top gear in her Games entrance on Sunday, albeit making it through to each of her finals, and there is no room for any slip-ups in the women's team final.

The Russian Olympic Committee finished above the United States at a major event for the first time since 2010 in qualifying, setting up an intriguing battle in the final.

The pressure is on Suni Lee, Jordan Chiles, Grace McCallum and indeed Biles, the latter of whom is aiming to add to the four golds won in Rio five years ago.

USA-JAPAN MEET IN SOFTBALL FINAL

Team USA's women's softball team recovered from behind to beat Japan 2-1 in their final round-robin game and finish top of the standings.

Japan finished second and the two sides are therefore set to face off in a huge gold medal match at Yokohama Baseball Stadium.

Mexico and Canada meet in the bronze medal contest earlier on Tuesday in a tasty warm-up match for the main event.

LEDECKY AND TITMUS RESUME RIVALRY

After winning four golds in Rio five years ago, Ledecky had the chance to add four more to her collection in Tokyo.

She fell short in the first of those events, however, with Australia's Ariarne Titmus taking gold in Monday's gripping 400m freestyle final.

While a medal is not on the line on Tuesday, Ledecky will be eager to lay down a faster time than her rival in the 200m freestyle heats ahead of Wednesday's showpiece.

OSAKA GOES AGAIN

Face of the Games Okaka followed up lighting the Olympic cauldron on Friday with victories over Zheng Saisai and Viktorija Golubic in her first two matches in the tournament.

The four-time grand slam winner has a quick turnaround in matches as world number 41 Marketa Vondrousova awaits in the third round on Tuesday.

Fellow home favourite Kei Nishikori is also in action in the men's event, with Marcos Giron standing between him and the last 16.

WOMEN'S TRIATHLON TOUGH TO CALL

There was drama before the men's triathlon had even officially got underway on Monday, with an inflatable boat carrying photographers causing a false start.

Norway's Kristian Blummenfelt won the competition and now it is over to the women, with 54 athletes in contention to claim gold.

The field is wide open this time around, though the likes of Katie Zaferes and Georgia Taylor-Brown, of Team USA and Great Britain respectively, will have their eyes on the top prize.

Another superb day for Japan saw the host nation surge to the top of the medal table at the Tokyo Olympic Games on Monday.

Japan now have eight golds after winning Olympic titles in three different sports, the most unexpected of which came in table tennis.

The mixed doubles team of Jun Mizutani and Mima Ito came from two games down to eventually prevail after seven games against China's Xu Xin and Liu Shiwen.

China won all four table tennis titles at Rio 2016 and had been expected to dominate again, only to come unstuck as Japan won the first gold in this new event.

Further joy for Japan came as 13-year-old Momiji Nishiya triumphed in the women's street skateboarding while Shohei Ono was victorious in the men's 73kg category in judo.

Second behind Japan are the United States, who took two shooting golds on day three as well as the men's 4x100m freestyle title in the pool.

China did not add to their tally of six gold medals, one fewer than the USA, having come up short in another event where they had a team of heavy favourites.

Cao Yuan and Chen Aisen were edged out in the men's 10m synchronised platform, with British divers Tom Daley and Matty Lee winning gold.

That was one of three golds for Great Britain, who moved up to fifth in the medal table thanks also to Adam Peaty retaining his 100m breaststroke title and Tom Pidcock dominating in the men's cross-country mountain bike race.

The Russian Olympic Committee sits fourth after adding three golds, the headliner being victory in the men's artistic gymnastics team all-around final. 

Meanwhile, Hidilyn Diaz made history for the Philippines, become the country's first Olympic gold medallist by prevailing in the women's 55kg weightlifting.

Adam Peaty revealed he has gone through "breakdowns" and has had to hide emotions from his family after becoming a double Olympic champion.

It was another dominant performance from world-record holder Peaty in the 100 metres breaststroke at the Tokyo Aquatics Centre, with a time of 57.37 – the fifth fastest in history – enough for him to make history as the first British swimmer to defend an Olympics title.

Peaty is unbeaten in the event in seven years and only one other swimmer has ever breached the 58-second mark – that being silver medallist Arno Kamminga.

Despite his dominance, Peaty spoke about the challenges he has faced, with the 26-year-old having become a father to his son George within the past year.

He said: "It's been a heavy investment. A lot has changed this last year, more than the last five. Becoming a father, buying my first house and some days when I woke up and was like 'this is hard, this is really hard'.

"There's been so many challenges, so many challenges and f*****g some breakdowns as well. 

"It's like 'what am I doing every single day? Why am I training three times a day, giving it everything for this swim?'.

"I've hidden a lot of emotion from my own family, I've hidden a lot of stress and a lot of those moments where I was like 'this is very, very hard'.

"The 99.9 per cent of time that we spend in the dark is for the 0.01 per cent we spend in light."

Having made history, Peaty was asked how much longer he foresees himself staying in the pool, with the Paris Games three years away.

"I think of sport very simply, as soon as I stop having fun I'll stop, I'm still having fun, I have a lot of fun with my boy, I have a lot of fun at home and having a normal life too," he added.

"It's such a big decision, it's a family decision now, not just me being a selfish athlete because we have to be selfish but we'll have that conversation when we're home. 

"Obviously, we're targeting Paris anyway, anything after that is a bonus really. It's about how young you keep your mind, sport is getting faster, the world is getting faster, you have to take that in to consideration too.

"It depends what else is out there, if I can inspire people in other ways I'll probably do that. But I live in the present."

Norway's Kristian Blummenfelt said he never had a doubt he would win the triathlon, and his confidence never wavered as he pulled away late to take the gold. 

The top contenders spent much of Monday's race biding their time, with all the favourites in the mix following the swim and bike legs, but Blummenfelt drove the pace on the final leg. 

When the lead group winnowed down to himself, Great Britain's Alex Yee and Hayden Wilde of New Zealand, Blummenfelt urged the 23-year-olds to keep the hammer down – then ran away from them in the end. 

One last kick over the final kilometre put Blummenfelt atop the podium, with Yee taking silver and Wilde bronze. 

"We were like 10 guys in the running lead and when he picked up the pace I saw that we were down to four and I tried to get [Yee] motivated to keep the pace," Blummenfelt told reporters.

"I said, 'Guys, we have a medal now, keep the gas on,' and I think that for Alex and Hayden this is a great moment to get an Olympic medal, too."

Yee's compatriot Jonathan Brownlee, who won silver in the event in Rio and bronze in London as his brother Alistair took gold in both races, finished fifth on Monday.

"I told myself last night that all I can do is try my hardest and before that, prepare," Brownlee said. "I did everything I could, I got ready for the heat, I trained as hard as I could, had a great team around me and that's all you can ask.

"I think I've been very, very fortunate in my two Olympic Games, I've had two medals. It's hard to perform and I've performed well in three." 

'NERVOUS' OSAKA KEEPS ROLLING

Playing for the second consecutive day, second-seed Naomi Osaka showed no signs of fatigue as she cruised to a 6-3 6-2 second-round victory over Switzerland's Viktorija Golubic on Sunday. 

Japan's big hope Osaka had to play back-to-back after having her schedule altered following the honour of lighting the Olympic cauldron Friday, and the other top women in action looked just as strong after a day off Sunday. 

"Honestly, I feel like I was a bit more nervous before the match," Osaka told reporters. "I felt a lot of butterflies, but I think as I started playing and feeling more comfortable, I knew that no matter what it would be a great match."

After pulling out of the French Open before the second round and skipping Wimbledon, the four-time grand slam winner has not had much match time over the last two months, but her goal in Tokyo remains the same. 

“It would mean a lot to win gold here, but I know it's a process," she said. "I know these are the best players in the world, and honestly I haven't played in a while, so I'm trying to take it one notch at a time.

"All in all, I'm just really happy to be here. I haven't been in Tokyo for a couple of years."

In other early matches, seventh-seeded Garbine Muguruza of Spain rolled past China's Wang Qiang 6-3 6-0, while eighth seed Barbora Krejcikova had a tougher time with Canada's Leylah Annie Fernandez before moving on 6-2 6-4 and 11th seed Anastasia Pavlyuchenkova defeated Anna-Lena Friedsam 6-1 6-1. 

MACNEIL EARNS CANADA'S FIRST GOLD

It took Margaret MacNeil a few moments to realise she had won Canada's first gold medal of the Tokyo Games.

The 21-year-old usually wears contact lenses but does not put them on when she is in the pool, so she had to focus to see her name atop the scoreboard after the 100m butterfly at the Tokyo Aquatics Centre. 

"I like to check the scoreboard pretty quickly, but it's hard just because I don't have contacts," she said. "It does take me a minute to read the scoreboard, so I was just trying to squint and see where I came."

Her vision problems may have been a benefit during the race, which saw her edge China's Zhang Yufei by 0.05 from lane seven. 

"I could hardly see anyone on the far side of the pool, which I think helped me a lot, because I was able to just focus on my own race," MacNeil said. "I just put my head down and tried to get to the wall as fast as possible. I'm really glad it all came together."

While MacNeil took the first gold medal in the pool Monday, her win was overshadowed by later events. 

Great Britain's Adam Peaty defended his Olympic title in the 100m breaststroke, while Ariarne Titmus of Australia dethroned the reigning champion Katie Ledecky in the 400m freestyle. 

In the final medal event of the day, Caeleb Dressel – Michael Phelps' heir apparent – and the USA won the 4x100m freestyle relay by 1.14 seconds over Italy. 

UPSETS ABOUND IN FENCING

Three of the top six women in the world were eliminated early in the women's sabre competition Monday. 

Top-ranked Olga Kharlan of Ukraine, twice a bronze medallist, fell to Yang Hengyu of China 15-12 in the round of 32 to end her hopes of a third straight medal. 

Fourth-ranked Shao Yaqi of China and world number six Anne-Elizabeth Stone of the USA went out in the same round. 

Sofia Velikaya of Russia, who took silver in Rio, remains alive heading into the quarter-finals later Monday along with 2016 fourth-place finisher Manon Brunet of France. 

REIGNING CHAMPIONS FIJI OPEN RUGBY SEVENS PLAY

Reigning gold medallists Fiji rallied in the second half to defeat Japan 24-19 in a rematch of the Rio 2016 semi-finals. 

Fiji trailed 19-12 but fought back through a pair of tries and a conversion from substitute Waisea Nacuqu in the final four minutes.

The team they beat for gold five years ago, Great Britain, opened play with a flourish, thrashing Canada 24-0, while New Zealand crushed South Korea 50-5. 

Fourth-place finishers in 2016, South Africa defeated Ireland 33-14 while Argentina beat Australia 29-19 and the United States edged Kenya 19-14. 

Ariarne Titmus said staying composed was the key to her victory over Katie Ledecky in a captivating women's 400 metre freestyle final.

In what was billed as one of the races of Tokyo 2020, both women produced a performance straight out of the top drawer in a battle that went down to the wire.

World champion Titmus was back by around six lengths at one stage as Ledecky stormed out of the blocks.

The American world record holder, who set her benchmark when winning gold at Rio 2016, would be reeled in by a determined Titmus, though, and the Australian held on to win a thriller.

"Honestly, at the 200 metre [mark] I was a bit worried, but I did not come to the Olympic Games unprepared," said Titmus, who became the third Australian woman to win gold in the event, after Lorraine Crapp and Shane Gould.

"I had to trust myself and stay as composed as I could. Use the speed that I have. And all that against a woman who has an amazing back end of her race. I'm really proud."

Titmus is also slated to race in the 200m and 800m free races at Tokyo 2020 and says the celebrations are on hold for now.

"It is the biggest thing you can pull off in your sporting career, so I'm over the moon," she added.

"I'm trying to contain it as much as I can. I have a big programme ahead of me, but I can enjoy this afterwards."

Ledecky had never been beaten in an individual Olympics race and swam her second ever fastest time in the 400m free.

The American concedes her rival was just better on the day.

"She definitely swam a really smart race. She was really controlled up front," Ledecky said.

"I felt smooth and strong. I looked up at 300m, and she was right there, so I knew it would be a battle to the end. I didn't feel like I died or really fell off. She just had a faster final 50 or 75m and got her hand to the wall first."

When asked if this was her toughest race, Ledecky, a five-time Olympic gold medallist, replied: "I guess. 

"I've had some tough ones over the years. It was certainly a tough race and I delivered. I couldn't do much better than that. 

"It was a tremendous race, a lot of fun. I can't be too disappointed. It was my second-best swim ever (over 400m freestyle). I felt like I fought tooth and nail and that's all you can ask for."

"Some days you've just got to attack the f*****g mountain, that's as simple as it is."

Those were the words of Adam Peaty during his pre-camp for Tokyo 2020. And boy has he attacked that mountain.

Five years ago, Peaty broke new ground to become an Olympic champion for the first time in Rio and set in motion a Team GB gold rush that would see them ultimately finish second in the medal table.

On this occasion, there was no world record – the only thing that is sure to secretly irritate this perfectionist who revels in finding new ways to push the limits of what is humanly possible – but not for the first time Peaty obliterated the competition to once again win Olympic gold in the 100 metres breaststroke.se

Whether his success can have the same sort of rousing effect on Team GB, only time will tell.

What is more certain is that Peaty must surely now be considered among the pantheon of Olympic greats.

At one stage in 2021, the 26-year-old was in possession of the 20 fastest 100m breaststroke times in history. It is mind-boggling dominance.

When the great Usain Bolt used to race there was a real awe about the way in which he had his opponents beaten by the time he was on the start line. It was mesmerising watching the sprint king, who just seemed to defy logic.

Peaty in the pool exudes a similar feeling. To witness this phenomenon in person is some experience. If you blink you might miss him.

Following his victory in the heats on Sunday, Peaty described Tokyo 2020 as "weird" without the crowds – with fans of course absent due to the coronavirus pandemic – and conceded it did "not feel like an Olympics".

He does have a point. Peaty's moment of triumph came on a day where Ariarne Titmus defeated Katie Ledecky in an epic to clinch the women's 400m freestyle – a race that really did deserve a full house – and Caeleb Dressel, tipped as an heir to American great Michael Phelps, won the first of what is likely to be multiple gold medals at these Games.

Such stars deserve a captivated audience. The cheers of their team-mates offered only slight consolation that their moments of glory are taking place in surreal circumstances.

But there is nothing strange now about seeing Peaty dominate in the pool and while the circumstances compared to his first crowning moment in Brazil could scarcely be more different, he continues to enhance his status as a supreme champion.

His latest victory was a moment of history – no British swimmer had ever defended an Olympic title before. Only three other swimmers from Britain have ever won multiple golds, and he is just the second man to defend the 100m breaststroke title after Japan's Kosuke Kitajima.

When you think of the great athletes Britain has produced – Steve Redgrave, Kelly Holmes, Chris Hoy, Laura Kenny, Jason Kenny – all belong in the category of elite Olympians.

That Peaty now too belongs in that same category is not even a debate. He is a cool competitor, but he is also a ferocious one. A contemplator, a thinker, a man who self-described himself as "liberated" by the circumstances of the past year, time that saw him become a father and learn to appreciate the important things in life as lockdowns and restrictions became the norm for us all.

What is scary is that you feel there is still new ground for Peaty, unbeaten in his event since 2014, to break.

Speaking prior to the Games, Peaty opened up about what makes him the athlete he is.

"It sounds very cliche but I'm very obsessed with continual improvement and pushing the boundaries of what's possible," he said then. 

"I don't want to end my career and go 'oh I could have done that or I should have done this'. It's that relationship with the team that makes me that person. But I think it's also I just love to race, I love to scrap and I like to dominate. That's why I swim, that's why I race it gives me something I can't get in normal life."

And even now with all he has achieved there still seems to be an unquenchable thirst to be the best, no taking the foot off the gas in a continued desire to go where no one has been before.

"No one is invincible, everyone can be beaten," he told a news conference following his victory in Tokyo.

"I'm a firm believer in that. If I didn't believe in that I wouldn't have the world record, it's about setting no limits. 

"Today could have gone either way. It's a morning final, you saw it this morning with such a close race with Ledecky and Titmus, it could have gone either way.

"Everyone is beatable, it's who wants it more and who is invested more in those races."

For most, owning the world record and becoming a double Olympic champion would be well beyond the pinnacle of the mountain.

For Peaty, it seems certain he will just keep on f*****g attacking it.

Ariarne Titmus defeated Katie Ledecky in a thrilling women's 400 metre freestyle final that lived up to its billing, while the brilliant Adam Peaty made history by becoming a double Olympic champion.

A star-studded cast in the pool at the Tokyo Aquatics Centre on Monday did not disappoint, with Canada's Maggie McNeil adding to her World Championship title in the women's 100m butterfly.

And in the men's 4x100m freestyle relay, Caeleb Dressel – tipped to be one of the stars of the pool – earned his first gold of the Tokyo Games.

TITMUS AND LEDECKY PUT ON A SHOW

The only disappointment about the women's 400m free was the fact no fans were in attendance to witness a battle for the ages.

The pre-race hype centred around whether it would be Ledecky, who had never lost in an individual Olympic event, or Australia's world champion Titmus that would be prevail.

Ledecky held a six-tenths lead after 200m and looked well on course to defending the title she won at Rio 2016 in a world-record time of 3:56.46.

But Titmus came storming back and a stunning 28.67 split on the way home was enough to fend off Ledecky – whose 3:57.36 was her second fastest time in the 400m free.

Titmus' 3:56.69 is second only to Ledecky's world record and she becomes the third Australian to win gold in the event.

PERFECT PEATY DOUBLES UP

There was no world record over three races for Peaty but his utter dominance of the men's 100m breaststroke shows no sign of abating as he became the first Briton to ever defend an Olympics swimming title.

Five years on from winning gold in a world-record time at Rio 2016 (a benchmark he has since beaten twice), Peaty swam a 57.37 to stand atop the podium again ahead of Arno Kamminga – the only other swimmer in history to go under 58 seconds.

It was perhaps not quite the time Peaty, who had designs on another world record, wanted but it still represents the fifth fastest time in history and edged his previous season best of 57.39.

Peaty unleashed an almighty roar after his win and later said to BBC Sport: "I haven't felt this good since 2016. It just means the world for me.

"Thank you to the nation for being behind me. This victory wasn't mine - it was a great swimming team, my family, my friends."

Peaty is now only the second man to defend an Olympic breaststroke title, and just the fourth swimmer from Great Britain to win multiple golds in the Games.

MAGIC MAGGIE

Maggie McNeil completed a world and Olympic double in the women's 100m butterfly in an incredibly tight race.

The Canadian was down in seventh but propelled towards the front after a brilliant turn and managed to hold off China's Zhang Yufei to earn gold. 

The top four all ranked inside the top seven swims in the 100m butterfly of all time, with McNeil's 55.59 the second fastest ever. Australia's Emma McKeon took third, with Torrie Huske of the USA just 0.1 off the podium.

DRESSEL UP AND RUNNING

America's big men's hope in the pool at these Games is Dressel, who has been touted as the successor to the legendary Michael Phelps.

The 23-year-old is top seeded in three individual events and raced in the first of potentially four relay events on Monday as the United States romped to victory in the 4x100m freestyle.

Joined by Blake Pieroni, Bowen Becker and Zach Apple, the US came home in a time of to 3:08.97, with Italy and Australian rounding out the podium. 

Elsewhere, Duncan Scott of Great Britain went fastest in the men's 200m freestyle (1:44.60) semi-finals ahead of American Kieran Smith (1:45.07), while world record holder Ryan Murphy led the way in the 100m backstroke semis.

In the women's 100m backstroke semi-finals, Regan Smith set an Olympic record time of 57.86 and Tatjana Schoenmaker went quickest in the women's 100 breaststroke semi-finals ahead of rival Lilly King.

Veteran swimmer Alia Atkinson shared a few words with her fans after her final race at the Olympic Games Tokyo 2020.

The Jamaican took to Instagram and wrote, “It’s funny. Looking back, the years went by so fast and before I realized it, I was looking at the end of it. A question that was asked after my swim today was: Would I give it all up for an Olympic medal? And honestly, I wouldn’t trade this journey for anything. All the ups and downs has made me who I am today (though at times it feels like there are more downs than ups), but it taught me how to get up and God taught me how to smile through it all."

 Atkinson, who made her Olympic debut in 2004, finished third in heat 3 of the Women’s 100m Breaststroke but only just missed out on a semifinal spot. She recorded a time of 1:07:70, which was the 17th fastest, meaning she finished just outside of the qualifiers, with only 16 places up for grabs. It was her only event of the Games.

 “My x5 Olympic journey ends here, but the Olympic medal is still waiting for some Jamaican girl/boy to claim it. I know you can, so keep pushing," she wrote.

 The 31-year-old has not won an Olympic medal for Jamaica, but one of her most notable performances was at the Olympic Games.  At London 2012, she finished fourth in the 100m Breaststroke. She beat Canada’s Tera van Beilen in a swim-off to make it to the final after the two were tied in the semifinal. She then went on to clock 1:06:93 in the final to become the second Jamaican to finish in the top four of an Olympic swimming event.

She ended her Instagram post by writing, “To the future Jamaican Olympic swimming medalist: “I hope the road was/is less rocky for you. If so, then I have indeed succeeded. We have waited a long time for you, so thank you for staying true and carrying the fly high."

Atkinson has indicated that she has not retired fully from swimming and this is just the end of her Olympic journey.

The third full day of the Tokyo Olympics sees 21 gold medals up for grabs during a packed programme.

Plenty of eyes will be on the Tokyo Aquatics Centre, where four swimming golds will be on the line, while the first women's skateboarding champion will be crowned.

The rugby sevens event gets under way and the men's triathlon will also take place.

Stats Perform picks out some of the standout action.

LEDECKY STEPS UP GOLD QUEST

After winning four golds in Rio five years ago, Katie Ledecky has the chance to add four more to her collection in Tokyo, starting with the women's 400m freestyle.

The United States competitor set a world record time in the event in 2016, but she will face a big challenge from Australia's Ariarne Titmus this time.

Titmus was marginally faster than Ledecky in the heats, though whether that edge will count for anything on the day remains to be seen.

WILL IT BE ANOTHER PEATY BLINDER?

Great Britain's Adam Peaty is nothing short of a phenomenon in the world of swimming and will be looking to retain his 100m breaststroke title.

Peaty qualified for the final in a dominant manner, his time of 57.56s just two hundredths of a second off his own world record pace.

Arno Kamminga of the Netherlands is expected to be Peaty's biggest threat, having produced a personal best of 57.80s in the previous heat.

MORE SEVENS HEAVEN FOR FIJI?

Fiji's triumph in the men's rugby sevens was one of the more remarkable stories of the Rio Games and the islanders will now be out to retain their title in Tokyo over the coming weeks.

They begin their group campaign on Monday with games against tournament hosts Japan and then Canada later in the day.

MEN'S TRIATHLON WIDE OPEN

The men's triathlon is a tough one to call, with back-to-back champion Alistair Brownlee not taking part in this year's event.

The likes of Alex Yee, Kristian Blummenfelt, Morgan Pearson and Tyler Mislawchuk are among those to watch in one the standout events at any Games.

BILES SURVIVES, NOW MEN MUST THRIVE

After Simone Biles struggled to find top gear in her Games entrance on Sunday, albeit making it through to each of her finals, Monday's gymnastics event is the men's team final.

Japan are the defending champions and led the way in qualifying, but they are expected to face stiff competition from China and the Russian Olympic Committee team. Watch out for Russian maestro Nikita Nagornyy and Japan's Daiki Hashimoto among a star-studded cast.

OSAKA BACK IN ACTION

It is proving to be a busy Games for Naomi Osaka, who followed lighting the Olympic cauldron on Friday with a first-round tennis win on Sunday.

Japan's four-time grand slam winner is back on court on Monday, looking to inch closer to the women's singles final. Awaiting her is Swiss world number 50 Viktorija Golubic, and it will be their first match encounter. Men's title hopefuls Novak Djokovic and Daniil Medvedev are among those also due in action.

WOMEN'S SKATEBOARDING MAKES ITS DEBUT

Japan's Yuto Horigome made history on Sunday by winning the first Olympic gold in men's skateboarding. On Monday, it is the turn of the women.

Among those competing in the event are Kokona Hiraki of Japan and Team GB's Sky Brown, who are aged 12 and 13 respectively.

After plenty of falls and drama in the men's equivalent, expect more of the same in this inaugural event. 

Barbadian swimmer, Alex Sobers, has set a new national record in the Men's 200m Freestyle.

Competing earlier today, Sobers smashed his previous record of 1:48.35, set earlier this year. The 22-year-old, swimming out of lane 7, in heat 2, finished in a time of 1:48.09 to finish 6th.  The heat was won by Romania’s David Popovici who touched home first in a time of  

1:45.32.  Second place went to Serbia’s Velimir Stjepanovic, who recorded a time of 1:46.26.  Both men advanced to the event’s semifinals.

For Sobers, the result follows up on the second-time Olympian’s 7th place finish in heat 2 of the Men’s 400m Freestyle yesterday. He finished in a time of 3:59.14 seconds. Sobers failed to advance to the semifinals in any of his events.

Meanwhile, his teammate, Danielle Titus also finished 6th in her heat today. The Olympic debutante hit the pool for the Women’s 100m Backstroke and finished with a time of 1:04.53. She did not advance to the semifinals. That was her only event.  The event was won by Moldova’s Tatiana Salcutan who was first in 1:01.59, with McKenna DeBever Elliot second in 1:02.09.