Japan remained top of the medal table at the Tokyo Olympics as they collected another three golds on day five.

Daiki Hashimoto, 19, was the standout performer as he secured a last-minute win in the men's all-around gymnastic final, with China's Ruoteng Xiao and the Russian Olympic Committee's pre-event favourite Nikita Nagornyy settling for silver and bronze.

That win took the host nation to 13 golds, with Chizuru Arai in the women's 70kg judo – their eighth medal in the sport at the Games so far – and Yui Ohashi in the women's 200m individual medley the other victors.

China pulled one clear of the United States as they also collected three golds on Wednesday. Shi Zhiyong broke his own world record to win the men's weightlifting 73kg event, while Wang Zongyuan and Xie Siyi brought China's third diving gold at the Games with victory in the men's synchronised 3m springboard final.

The USA had to settle for silver in China's diving win, though they did pick up gold in the debut 3-on-3 women's basketball event by defeating the Russian Olympic Committee.

Katie Ledecky and Erica Sullivan captured an American one-two in the women's 1500m freestyle meaning only Michael Phelps (13) has more individual Olympic success than Ledecky.

The Russian Olympic Committee remain fourth despite not winning gold on a frustrating day that saw them finish runners-up in both 3x3 basketball events and the men's 4x200m freestyle relay.

Australia enjoyed a memorable day in rowing as they battled to back-to-back golds in both the male and female coxless four, with Ariane Titmus setting a Games record in the women's 200m freestyle to move the Australians up to six golds.

Due to Australia's success on the water, Great Britain's dominant five-gold run in the men's coxless four that stretched back to Sydney 2000 came to an end, though they did collect a first silver medal in men's quad sculls.

Tom Dean, who won gold on Tuesday, was part of the men's 4x200m freestyle team that picked up Team GB's only gold of the day as they moved down to sixth place.

Ash Barty has followed up her shock women's singles defeat by crashing out of the women's doubles after an epic clash with Czech pair Barbora Krejcikova and Katerina Siniakova.

World number one Barty was stunned in the first round of the women's singles on Sunday by Spain's Sara Sorribes Tormo but teamed up with Storm Sanders in the doubles, with the Australian pair reaching the quarter-finals.

However, Krejcikova and Siniakova proved too strong in a three-set thriller, winning 3-6 6-4 10-7.

"You never quite have their measure,” Barty said. "It's disappointing but there's only a couple of points in that match, here and there and it's a different result.

"We did everything right today but just weren't able to win those big points when it mattered most."

Barty's medal hopes are now entirely focused on the mixed doubles, where she has partnered with John Peers.

Andy Murray's bid to become the first male to win four Olympic tennis medals ended with defeat to Croatia's Marin Cilic and Ivan Dogic in the men's doubles.

Murray, teaming up with Joe Salisbury, went down in two hours and 18 minutes after also winning the first set. The Croatian pair won 4-6 7-6 (7-2) 10-7.

The two-time Olympic gold medalist had withdrawn from the men's singles on Sunday due to a right quad injury, preferring to focus on playing doubles. TeamGB have not fielded a mixed doubles team.

TITMUS DOUBLES UP, LEDECKY LIFTS FOR GOLD

Ariarne Titmus backed up her women's 400m freestyle gold medal from Monday with another triumph, getting the better of rival Katie Ledecky to win the 200m free.

The 20-year-old Australian won the final ahead of Hong Kong's Siobhan Bernadette Haughey and Canada's Penny Oleksiak, while Ledecky finished back in fifth.

Ledecky would claim her sixth Olympic gold medal, triumphing in the women's 1500m free, with the US claiming a rare one-two as Erica Sullivan grabbed the silver ahead of Germany's Sarah Kohler.

After being beaten twice by Titmus earlier in the meet, Ledecky said: "I approach each race with a belief in myself. It's the attitude I've always had that's why I've been so successful. Anything can happen, [the attitude I go in with is] I can beat the world record in this race. 

Japan's Yui Ohashi won the women's 200m individual medley, Hungarian favourite Kristof Milak powered to victory in the men's 200m butterfly and Great Britain triumphed in the men's 4x200m freestyle relay.

STEERING ERROR COSTS GB IN ROWING

Australia claimed two gold medals in the rowing at Sea Forest Waterway as Great Britain were left to lament a wayward finish in the men's four final.

Australian quartet Alexander Purnell, Spencer Turrin, Jack Hargreaves and Alexander Hill won in 5:42:76 ahead of Romania and Italy who claimed silver and bronze respectively.

Italy's late charge almost saw a collision with Great Britain, who finished in fourth, after veering towards the neighbouring Italian boat, narrowly avoiding a clash of oars.

GB's Oliver Cook, who steered the men's coxless four, told BBC Sport: "I do (have the steering). I need to diagnose it but I feel I screwed up a bit and as I was closing in at the end and taking big strokes at the end going for the line I forgot the steering and that’s what cost us to be honest, cost us a medal."

Australia also won the women's four narrowly ahead of the Netherlands by 0:34 seconds, with Ireland claiming the bronze more than five seconds back.

Romania secured its first gold medal at the Tokyo Olympics by winning the women's double sculls final, while France triumphed in the men's equivalent.

The Netherlands and China triumphed in the men's and women's quadruple sculls finals respectively.

RADRADRA DREAMING OF FIJI SEVENS GOLD

New Zealand will take on 2016 gold medalists Fiji in the final of the men's rugby sevens on Wednesday evening.

Fiji went through to the gold medal match with a 26-14 triumph over Argentina, who will take on Great Britain for bronze.

New Zealand were too strong for the British, winning 29-7 in their semi-final, with two tries each to captain Scott Curry and Regan Ware.

Former NRL star Semi Radradra, who plays for Fiji after switching codes in 2017 and scored a try against Argentina, said: "Playing in the Olympics is a blessing for me. I never knew I would be here.

"I think it is everyone's highlight to win a gold medal in the Olympics. That is our aim and we try to give back to our people at home."

USA RESTORES CONFIDENCE IN BASKETBALL

Team USA restored some confidence following their first-up loss to France with a comprehensive 120-66 thrashing of Iran in men's basketball.

USA played fast throughout, wasting no time in offense, with Damian Lillard top scoring with 21 points, all from beyond the arc.

Chicago Bulls guard Zach LaVine had eight assists along with his 13 points while Devin Booker, who played in the NBA Finals last week, scored 16 points and had five rebounds and three steals.

USA head coach Gregg Popovich rotated his roster on and off the court, sharing minutes, as hos team piled on 38 points in the last quarter to round out a comprehensive victory.

In Group B, Germany defeated Nigeria 99-92 despite Jordan Nowra's 33-point haul.

Katie Ledecky called on a source of inspiration close to home as she ended her wait for a gold at the Tokyo Games with victory in the women's 1500m freestyle final.

Ledecky, who Olympic great Micheal Phelps hailed as "the best female swimmer that we have ever seen", had endured a frustrating start to the Games, failing to defend the 200 metre and 400m free golds which she won at Rio 2016.

Australia's Ariarne Titmus has instead enjoyed the breakthrough to stardom this time around, but Ledecky finally struck gold in Tokyo as she powered to glory in the maiden women's 1500m event.

It took her total of Olympic golds to six – the 24-year-old becoming the fourth female swimmer to reach that mark, after compatriots Jenny Thompson (eight) and Amy van Dyken (six), and Germany's Kristin Otto (six).

Ledecky, who clocked in at 15:37.34, is also just the fourth American woman to claim six golds, after Thompson, Van Dyken and Allyson Felix.

Erica Sullivan clinched silver to seal a one-two for Team USA, and Ledekcy revealed her thought process following a disappointing fifth-place finish in the 200m race.

"After the 200, I knew I had to turn the page very quickly and in the warm-down pool I was just thinking of my family," said Ledecky, who has now won gold medals at three different Games, following success in London, at the age of 15, and Rio.

"Each stroke I was thinking of my grandparents. They're the toughest four people I know and that's what helped me get through that.

“It means a lot. People maybe feel bad that I'm not winning everything, but I want people to be more concerned about other things in the world. People are truly suffering. I'm just proud to bring home a gold medal to Team USA.”

Sullivan's silver handed the USA's first one-two finish in a women's swimming race since Sydney 2000, when Brooke Bennett and Diana Munz wrapped up the top prizes in the 400m freestyle.

“I'm so happy to go one-two with Erica," Ledecky added. "It is the first women's 1500m (freestyle in Olympic history) so I couldn’t have a better outcome than that. I’m so, so happy."

Sarah Kohler completed the podium to become the first German swimmer to win an Olympic medal since 2008.

One of the enduring images of Tokyo 2020 will be the sight of Dean Boxall's exuberant celebrations after Ariane Titmus won an epic women's 400 metres freestyle race.

It was the sheer joy and exuberance on the face of the rock-star looking coach as he wildly revelled in the momentous achievement of his pupil, who had just toppled the great Katie Ledecky in the most sensational fashion.

"I can't help it. I bleed with my athletes. When they leave the pool deck with me – whether I'm having a chat with them for an hour if it has to be – but when they leave, they have to start the recovery process and go home. They switch off. I don't. I go home and dream for them. I go home and try and find a way for them to get better," Boxall explained after he had gone viral on social media.

Titmus herself saw the funny side.

"That's just the way Dean is," she said. "He's very passionate about what he does – he really becomes quite animated.

"This is just as much for him as it is for me. He has sacrificed a lot in his family life, his kids and his wife, for his job. He puts 100 per cent into being a swimming coach. I would not be here without him."

But it was something else Boxall said that really went furthest to explaining his emotional display.

"I've been with her for five years. Having a dream together. Katie was so far in front of us that in the beginning when I started to coach her I couldn't even have this conversation," he said.

"When Arnie came to me she was a 4.12 [in the 400m]. At that stage Katie went 3.56. That's 16 seconds. We just started chipping away, we started to believe."

From a dream, to belief, to the reality of being an Olympic champion.

On Wednesday, Titmus would confirm her status as a breakout star of Tokyo 2020 with another victory in the 200m free filled with fight, desire and a never-say-die attitude.

Billed as Titmus versus Ledecky II, there was a sense of deja vu about Litmus' performance but another battle with her equally brilliant rival – now a six-time gold medallist over three Games after winning the first ever Olympics women's 1500m race – failed to transpire as the American could only finish fifth.

Instead it was Hong Kong's Siobhan Haughey who brought the very best out of Titmus. It took a huge effort down the final 50m to break the Olympics record in a time of 1:53.50.

At the medal ceremony there were tears and a warm embrace with Boxall, the emotion spilling out of this cool customer after becoming just the third Australian, along with Shane Gould and Ian Thorpe, to complete a 200 and 400m free double at a single Olympics.

"I feel like I'm pretty good at containing my emotion I knew that's something I had to do after the 400 because the 200 was right after," Titmus told a news conference after doubling up.

"Now that I haven't got a swim tonight I think I kind of let it out a bit, seeing him [Boxall] and seeing him emotional makes me emotional because this is a great partnership, this isn't just me winning, this is him winning so I think that's why I got so emotional."

For the uninitiated, this week is not the first time Titmus has triumphed over Ledecky, the 20-year-old from Tasmania having taken out the gold at the 2019 World Championships in Gwangju.

But Ledecky, who had won the 200 and 400m free at Rio in 2016, had been contending at that meet with a stomach virus and prior to this week it was far from certain where the golds were headed.

Titmus has emphatically answered the question, though, and it is her personable qualities that have made her resonate this week.

So too have the ferocity, tenacity and sheer awesome speed of her performances.

The Aquatics Centre, as Titmus herself adhered to when addressing the media, provides about as close to a normal experience as you're likely to find at Tokyo 2020. While there are still swathes of empty seats in this 15,000 capacity venue, there are areas designated to team-mates and coaches – all cheering, chanting and applauding to create at least some semblance of an Olympics atmosphere. 

But it is Litmus' displays that have brought true electricity, not only to the pool but for the Games at large.

Two more chances at gold lie in wait in the 800m (where Ledecky, a gifted long-distance swimmer, is favourite) and the 4x200m freestyle relay.

Regardless of what happens in those races, a new star has been born.

Ariarne Titmus stole the show again in the pool at Tokyo 2020, while Yui Ohashi also doubled up and Katie Ledecky got herself on the gold trail.

Australia's Titmus was back competing against Ledecky just two days on from their epic in the 400m free, though the latter was not in medal contention this time in the shorter 200.

However, the American – who has previously described herself as a "distance swimmer with a sprinter's mentality" – did become a six-time Olympic gold medallist on Wednesday.

Here's a round-up from the Tokyo Aquatics Centre.

TERRIFIC TITMUS DOUBLES UP

Wednesday's 200m freestyle race was billed as Titmus versus Ledecky II, with the former upstaging her American rival in the 400m free in a thriller two days earlier.

This time Ledecky was off the pace down in fifth and it was Hong Kong's Siobhan Haughey providing the test as Titmus had to pull one out of the bag again to get the gold.

A storming last 50m propelled her to a new Olympic record time of 1:53.50 and cemented her status as a breakout star.

"I could see I was trying to mow Siobhan down on the third 50. I had no idea where she was on the last lap. I knew I had Penny [Oleksiak, bronze] covered but Siobhan was the person that was there," Titmus said.

"I felt a little bit that was there. I felt a little bit - my legs started to go a bit but I'm happy to get it done."

Titmus joins Shane Gould and Ian Thorpe as the only Australians to complete a 200/400m freestyle double at a single Games.

JOY OF SIX FOR LEDECKY

She may have been unable to retain two of her titles from 2016 but the awesome Ledecky added to her gold medal haul with a dominant win in the first ever women's 1500m free Olympics final.

The American came home in 15:37.34 to lead a US one-two from Erica Sullivan.

Ledecky has now won gold medals at three different Games, having also topped the 800m free podium at London 2012.

OHASHI MARVELS IN IM ONCE MORE

Another star of these Games has been Ohashi, who will have delighted the Japanese fans watching at home after adding to her 400 individual medley crown in the shorter 200m race.

A race tipped to be wide open proved to be so with Ohashi battling stroke-for-stroke down the final 50m with American Alex Walsh, who was pipped by just 0.13 seconds.

Walsh's compatriot Kate Douglass rounded off the podium in third.

MILAK MAULS RIVALS

You can never be fully certain of an outcome in any sport but Kristof Milak was about as close to a shoo-in in the men's 200m butterfly as you can get.

So it proved to be. The Hungarian at least had the good decency to allow his rivals to believe they had a chance before absolutely blasting them out the water with his trademark finishing power.

Milak came home in a time of 1:51.25, a new Olympic benchmark and only half a second off his own world-record time. Japan's Tomoru Honda took silver from lane eight, some 2.48 seconds adrift.

DOUBLE DELIGHT FOR DEAN AS TEAMGB STAR IN RELAY

There was to be no record for TeamGB in the men's 4x200 free but they utterly dominated the competition to bring home gold in a time of 6:58.58.

Tom Dean, champion over the distance in the individual race on Tuesday, anchored the first leg before James Guy hit the front on his stint.

Matt Richards further stretched the advantage and Duncan Scott – who took silver behind Dean – brought it home in style with the Russian Olympic Committee over three seconds behind to take silver.

Australian swimming star Ariarne Titmus says her gold medal winning heroics are yet to fully sink in after de-throning Katie Ledecky to win the women's 200m freestyle on Wednesday.

Titmus edged out Ledecky in Monday's women's 100m freestyle final and backed that up with her second gold medal at the 2020 Tokyo Olympics.

The Australian won in 1:53:50, setting a new Olympic record, as she edged out Hong Kong's Siobhan Haughey by 0.42 seconds.

Canada's Penny Oleksiak claimed bronze, with five-time Olympic gold medallist Ledecky finishing down in fifth.

Titmus looked calm and composed in the pool after winning her second gold, with further races to come into the 4x200m freestyle relay and 800m freestyle.

"I don’t think it'll settle in until I get home and have a rest," Titmus told Australian TV network 7 after the race. "When you're in this situation you have to compartmentalise everything.

"I think once I stop racing, I think I'll release everything. On to the relay and 800m now. I don't want to ruin the rest of my meet by celebrating too hard. I'm proud with what I've achieved."

Haughey led Titmus at the final turn but the Australian stormed home over the last 50m, similar to Monday's win over Ledecky, although she said her "legs started to go".

"I was trying to mow Siobhan down in the third 50," Titmus said. "I had no idea where she was in the last five.

"I knew I had Penny covered but Siobhan was the person that was there. At the end my legs started to go but I'm happy to get it done."

She added: "Before we left, Sydney went into lockdown, it's really sad. I'm happy that the Olympics are here and we can hopefully bring some excitement to loungerooms.

"I'm fortunate to be here. I'm from a small town in Tassie [Tasmania]. It goes to show, if you believe you can do something, you can 100 per cent do it if you work for it."

Host nation Japan remain top of the Olympic Games medal table, one gold medal clear of the United States and China, thanks to another two gold medals on Tuesday in Tokyo.

Japan now have 10 golds at the Games, five of which have come in Judo, despite home favourite Naomi Osaka crashing out to Czech world number 42 Marketa Vondrousova in the women's singles tennis.

The USA extended their gold medal count to nine, with 17-year-old Lydia Jacoby stealing the headlines courtesy of gold in the 100m breaststroke – their third in the pool so far – though they had to settle for silver in softball as they lost to table-toppers Japan.

China, who have dominated the shooting to win eight medals in nine events, picked up three more golds with success in the 10m air pistol mixed event, the 10m air rifle mixed event and the women's 10m synchronised platform - their second diving gold in Tokyo.

The Russian Olympic Committee remain fourth with seven golds after winning the day's big event, the women's team artistic gymnastics, but that was overshadowed due to American Simone Biles withdrawing due to concerns over her mental health.

The Russians surprised in the pool, too, with Evgeny Rylov claiming 100m backstroke gold that forced defending Olympic champion Ryan Murphy to settle for bronze – that result represented the USA's first backstroke defeat since the 1992 Barcelona games.

After team-mate Adam Peaty's call for a British gold surge, Tom Dean and Duncan Scott made history by winning the first British swimming one-two since 1908 in the 200m freestyle.

Dean and Scott's swimming achievements capped a positive day for Great Britain that saw them collect six medals in total to stay in fifth place.

Meanwhile, Flora Duffy made history for Bermuda with gold in the women's triathlon as the tiny Caribbean island became the smallest country to ever win Gold at the Summer Games.

There was plenty of drama in Tokyo on Tuesday and that is set to continue as the Olympic Games ramps up further on Wednesday.

A titanic tussle in the swimming pool should be well worth watching, but action on the bikes and in the basketball court will also draw plenty of eyes.

Stats Perform guides you through the events not to be missed.

TITMUS OUT TO TOP LEDECKY AGAIN

Katie Ledecky is one of the dominant forces in the pool, taking gold in each of her prior four individual Games finals since her 2012 debut as she headed to Tokyo, but she was upset in the 2020 opener.

Ariarne Titmus, the 20-year-old Australian, beat the United States' world record holder by more than half a second in the 400m freestyle final.

Now, Titmus is coming for Ledecky's crown again as the pair do battle in the 200m freestyle, where another victory would send a significant message.

TOUR STARS TAKE ON TIME TRIAL

There are no shortage of big names in the men's time trial, with a number of Grand Tour winners involved – including Geraint Thomas, no doubt determined to put on a show after his fall in the road race.

The last two men to head out perhaps represent the most likely Olympic champions, though, as Wout van Aert and Filippo Ganna go for gold.

Van Aert won the final two stages of the Tour de France, including a time trial on the penultimate day of the race.

FOCUS ON THE FOUR

The first rowing medals of the Games are to be handed out on Wednesday, and the women's four – back in the Olympics for the first time in 30 years – should provide plenty of intrigue.

World champions Australia changed their line-up for the Olympics, having not competed internationally since taking their title in 2019. Meanwhile, the Netherlands, world silver medallists and back-to-back European champions, have been dominant.

The two teams won their respective heats, but Australia's time of six minutes and 28.76 seconds was an Olympic best and almost five seconds quicker than the Dutch. Whether that chasm will remain when the boats are side by side is another matter.

TWO-WAY TUSSLE IN THE GYM

There is more gymnastics action to look forward, with the men's individual final taking place.

Home hope Daiki Hashimoto qualified with the best score and was outstanding for Japan in the team event, yet could only take silver as the hosts were pipped by the Russian Olympic Committee.

It was Nikita Nagornyy's floor routine which sealed that Russian success and he will be bidding for another gold, having trailed Hashimoto in second in qualification.

CAN DREAM TEAM RECOVER FROM NIGHTMARE START?

The United States' latest men's basketball title defence started in miserable fashion with a defeat to France, the team who eliminated them at the 2019 FIBA Basketball World Cup.

It was Team USA's first Olympics loss since 2004, but it is highly unlikely a second will follow as they face Iran. A big performance is needed regardless to calm the critics.

While France delivered the upset in the basketball, they face their own humiliation in the football. Only a two-goal win against hosts Japan, themselves needing a point, will secure progress through Group A for Les Bleus.

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.