Naomi Osaka saw her Olympic gold medal dream shattered by a third-round defeat to Marketa Vondrousova at Tokyo 2020 on Tuesday.

Osaka lit the Olympic cauldron on Friday and was widely hailed as the 'face of the Games', with enormous expectation that she would go on to triumph for hosts Japan.

The early exit of world number one Ash Barty seemed to help her case, but Osaka lost 6-1 6-4 to her Czech opponent in an hour and eight minutes.

Osaka played a dismal opening set but then looked to have raised her game a notch in the second, establishing an early break.

However, that did not herald a full-blown fightback as former French Open runner-up Vondrousova soon got back on level terms and forced Osaka to serve to stay in the contest.

From 15-40, Osaka saved two match points, but Vondrousova soon had a third opportunity and her spirited defence won out.

Osaka flung a backhand wide this time and Vondrousova had her prized scalp, securing a place in the quarter-finals at the expense of the world number two.

It was an untidy performance from Osaka who made 32 unforced errors to just 10 from Vondrousova.

This was Osaka's first tournament since pulling out of the French Open at the end of May, in the wake of a first-round win. She cited depression and anxiety issues in Paris after announcing she would not take part in news conferences during the tournament.

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.

Naomi Osaka saw her Olympic gold medal dream shattered by a third-round defeat to Marketa Vondrousova at Tokyo 2020 on Tuesday.

Osaka lit the Olympic cauldron on Friday and was widely hailed as the 'face of the Games', with enormous expectation that she would go on to triumph for hosts Japan.

The early exit of world number one Ash Barty seemed to help her case, but Osaka lost 6-1 6-4 to her Czech opponent in an hour and eight minutes.

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.

Naomi Osaka is taking things "one notch at a time" at Tokyo 2020 after another convincing performance in round two on Monday.

With Ash Barty having suffered a shock exit a day prior, Osaka is now the favourite for glory on home court and with Aryna Sabalenka and Iga Swiatek among the round-two casualties that status is sure to only be enhanced.

There was better news for Elina Svitolina and Karolina Pliskova at the Ariake Tennis Park, though, in a women's draw stacked with top-tier talent.

OSAKA NOT GETTING AHEAD OF HERSELF

Back after a self-imposed two-month hiatus, defending US and Australian champion Osaka has not missed a beat and was too good for Viktorija Golubic in a 6-3 6-2 victory.

Osaka won 24 of 26 service points in the first set and 37 of 45 in the second, facing break point only once in a one-sided affair.

"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."

Svitolina was not as comfortable with the fourth seed rebounding from losing the opening set to defeat Ajla Tomljanovic 4-6 6-3 6-4. Maria Sakkari (14) awaits in the next round.

Carla Suarez Navarro earned her first win since recovering from cancer in round one and battled valiantly against Karolina Pliskova (5) before eventually losing in three sets.

Garbine Muguruza (7), Barbora Krejcikova (8) and Belinda Bencic all coasted through in straight sets, as did Anastasia Pavlyuchenkova (13) and Elena Rybakina (15).

TEARS FOR IGA 

Swiatek, whose father was an Olympic rower, would have had strong designs on a deep run at the Games but was beaten 6-3 7-6 (7-4) by Paula Badosa.

The Pole was left in tears after the defeat, and was still sobbing at her chair several minutes after the end of the match.

Sabalenka also bit the dust, going down in three sets to Donna Vekic, while Petra Kvitova lost the deciding set of her tie with Alison Van Uytvanck 6-0 to bow out with a whimper.

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. 

Ash Barty says she will keep fighting for an Olympic gold medal despite her shock opening-round defeat by Sara Sorribes Tormo in Tokyo.

The world number one fell at the first hurdle at Arianke Tennis Park, going down 6-4 6-3 against her Spanish opponent.

There were no such problems for Naomi Osaka; the home favourite overcame China's Zheng Saisai in straight sets.

BARTY TO KEEP FIGHTING FOR GOLD MEDAL

Crowned Wimbledon champion this month, Barty was unable to build on that momentum; amassing a whopping 55 errors.

World number 48 Sorribes Tormo took full advantage to set up a second-round showdown with France's Fiona Ferro.

Naomi Osaka is feeling "a little bit refreshed and happy again" after returning to tennis with a convincing 6-1 6-4 triumph over Zheng Saisai in her Tokyo 2020 opener.

The four-time grand slam winner has not featured since the first round of the French Open two months ago where she abandoned her campaign following a warning she risked expulsion over her refusal to take part in news conferences during the tournament.

Osaka, who is the reigning US and Australian Open champion, then decided to skip Wimbledon after opening up on her battles with anxiety and depression.

The 23-year-old was granted the honour of lighting the flame for Tokyo 2020 on Friday and two days later made a successful return at the Ariake Tennis Park, where she represents one of Japan's greatest medal hopes for the Games.

"I feel like, more than anything, I'm just focused on playing tennis. This, playing the Olympics, has been a dream of mine since I was a kid, so I feel like the break I took was very needed," she said.

"But I feel definitely a little bit refreshed and happy again.

"I felt really nervous being in Japan and playing here for the first time in maybe two years, and for it to be my first Olympics. 

"It was definitely really nerve-wracking. But I am glad I was able to win, she is a very tough opponent.

"It's been a while since I played but I feel, more than anything, just happy to be out here. We are playing in a pandemic, and it is really tough for everyone."

Asked how she felt to be talking to the press again, she said: "For me, honestly I don't feel that weird about it.

"It might feel weird to you guys, but I don't know. I'm happy that I guess you guys are asking me questions but more than anything I was just focused on playing tennis and I guess I feel a little bit out of my body right now."

Osaka then revealed that her starring role in Friday's opening ceremony came about in March.

"I was super honoured," she said. That’s a position you dream about and not anyone can do it so when they asked me if I wanted to I was very surprised but very honoured and I'm just happy to be here and happy to play, especially in Tokyo."

The playing conditions have been a quite literal hot topic over the first two days, with the sweltering heats causing issues for players.

Daniil Medvedev and Novak Djokovic were among those to speak out about the decision not to play matches later in the day Tokyo, where temperatures have regularly been above 30 degrees.

Osaka, though, has no such issues, adding: "It feels fine for me. I have played a couple of tournaments here, of course they resurfaced it since I was last here, but I love being here, and I actually really like the weather."

Naomi Osaka lighting the Olympic cauldron will have helped increase the exposure for the sport of tennis around the world, according to Novak Djokovic.

Osaka was given the honour of carrying the torch on the short final leg at the Japan National Stadium before walking the steps to light the flame and end the opening ceremony.

The four-time grand slam champion is the face of the Tokyo Games in her home country, creating extra pressure on her shoulders as she bids to strike gold.

Djokovic appreciates the absences of legendary names Roger Federer and Rafael Nadal is a blow, but he believes Osaka's presence is crucial for tennis in the battle for media coverage at the Games.

"It cannot be better for our sport, you are representing yourself, your country but also your sport in the Olympic Games, you're trying to get the hype and the attention towards our sport as much as you possibly can, so we're all contributing to that in the Olympic Village," Djokovic said when asked about Osaka's role in Friday's ceremony.

"There's a lot of attention towards the tennis players which is great, from the other athletes which is very nice to see, very nice to experience.

"Obviously you don't have Roger or Rafa. They are big stars and legends of our sport, but still there's quite a lot of great athletes, top players. Naomi is a home favourite and a lot of eyes are on her.

"Being at home playing is a lot of pressure, but it's great for our sport just in general to see that there's a lot of attention towards it."

Djokovic was speaking after overcoming Hugo Dellien with ease in his opening outing in the men's singles tournament, the Serbian triumphing 6-2 6-2 in just over an hour.

The quick win allowed the recently crowned Wimbledon champion to avoid staying out for too long in the Tokyo heat, an issue that led to Daniil Medvedev calling for matches to be pushed back to later in the day, allowing players to compete during the evenings when the temperatures have dropped.

"I agree with him 100 per cent," Djokovic said of Medvedev's suggestion. "I actually asked as well.

"My team captain, Viktor Troicki, was speaking to the referee a couple of times. To be honest, I don't understand why they don't start matches at say 3pm.

"I've heard for tennis there is some kind of curfew they have to finish at midnight, but if that's the case, I've just finished the last match and it's not even 5pm, we still have seven hours to play. 

"They have lights on all the courts, they're going to make life much easier for all of us tennis players, I just don't understand why they don't move it. 

"It's actually for the television broadcasters even better, because the later you play, the better it is for the United States and the time zones in Europe.

"I don't know, maybe the ITF (International Tennis Federation) can give you a better answer to why they chose to be played in the middle of the day. I doubt they will change the decision, but we're hoping that they will."

Naomi Osaka will make her playing entry to the Olympic Games a day later than expected after her first-round tennis match was put back to Sunday.

Japan's big hope for gold will play China's Zheng Saisai in her opener at the Ariake Tennis Park.

The match was billed to be first on the centre court at 11:00 local time on Saturday, only for Games organisers to announce it has been moved back by a day.

The move came amid mounting expectation that Osaka would have a prominent role to play in Friday's opening ceremony, meaning she would have little time to rest between taking part in that event and playing Zheng.

Osaka abandoned her French Open campaign after one match, having been warned she risked expulsion for refusing to take part in news conferences during the tournament.

The reigning US Open and Australian Open champion, who has spoken of struggling with anxiety and depression, then elected to skip Wimbledon.

Ash Barty and home favourite Naomi Osaka start their respective quests for Olympic gold against Sara Sorribes Tormo and Zheng Saisai, while Novak Djokovic opens against Hugo Dellien.

In a stacked women's draw, world number one and Wimbledon champion Barty has a tough opening assignment and could face French Open finalist Anastasia Pavlyuchenkova, the 13th seed, as early as round three.

Spectators may not be in attendance at Tokyo venues for the Olympics but Japanese fans will be rooting for Osaka, who returns to action after a two-month hiatus with the four-time grand slam winner having spoken openly about mental health and anxiety issues.

Viktorija Golubic or Maria Camila Osorio Serrano would await Osaka if she can get through round one, but a dream final with Barty is no shoo-in given 15 of the world's top 20 on the WTA Tour are in action including each of the nine leading the race for the 2021 WTA Finals.

Aryna Sabalenka (3), Elina Svitolina (4), Wimbledon runner-up Karolina Pliskova (5), Iga Swiatek (6) and Garbine Muguruza are all featuring in Tokyo.

The men's side has been hit by a spate of withdrawals, with Rafael Nadal, Roger Federer and Dominic Thiem among those not playing in the Japanese capital.

The main talking point surrounds whether the all-conquering Djokovic can continue his march towards a calendar Golden Slam – a sweep of all four majors and an Olympic gold in the same year.

Any notion of a free ride for the Serbian is wide of the mark, though. His side of the draw could see him come up against Andrey Rublev (5), Alexander Zverev (4) and Hubert Hurkacz (7), while Stefano Tsitsipas (3) – beaten by Djokovic in the French Open final – and Daniil Medvedev (2) are among the potential final opponents.

Andy Murray, gold medal winner in 2012 and 2016, faces Canada's Felix Auger-Aliassime in a tricky first-round match.

Novak Djokovic has leapt from one bubble into another as he attempts to become the first man in tennis history to win all four grand slams and Olympic gold in the same year.

The only men to have won each of the singles majors across their careers, plus Olympic gold, are Andre Agassi and Rafael Nadal, and now Djokovic aims to move to the brink of winning all five in his remarkable 2021 season.

Fresh from dominating at Wimbledon, and with the Australian and French Open titles already in the bag, Djokovic heads into the Tokyo Games as a red-hot favourite, seeking to set himself up to complete a historic campaign at the US Open.

Naomi Osaka will enter the Games with almost as much expectation behind her too, the reigning US Open and Australian Open champion eyeing glory for hosts Japan.

But tennis has thrown up a host of shock results in its short Olympic history. Here, Stats Perform looks at the sport's place in the Games.

WHO'S IN, WHO'S OUT, AND WHAT DOES ALL THIS MEAN?

Serena Williams, Roger Federer and Rafael Nadal have all opted out of the Olympics.

Williams made her mind up prior to suffering a leg injury at Wimbledon, although she is already a member of the career Golden Slam club.

Federer reached his decision after revealing he also suffered a physical setback at the All England Club, and Nadal elected to take a two-month break after relinquishing his French Open title.

Don't expect to see them again at the Olympics, given Williams and Federer will be pushing 43 by Paris 2024, and Nadal will be 38. Federer won a doubles gold with Stan Wawrinka in 2008, but his singles peak was the silver medal he earned in 2012, Andy Murray crushing Swiss hopes in the final at Wimbledon.

Dominic Thiem, Bianca Andreescu, Nick Kyrgios, Simona Halep, Angelique Kerber, Victoria Azarenka and Denis Shapovalov are among other confirmed absentees, with fitness issues a factor for some, less so for others.

The COVID-19 crisis is a mitigating factor in why so many stars are staying away, and directly responsible in the case of some players, such as Britain's Johanna Konta and Dan Evans, who both tested positive recently.

But tennis was only fully restored to the Olympic programme in 1988, after being dropped post 1924, and if players are seen to be favouring the grand slams over the Games, that is not such a great look for the sport.

At a time when the International Olympic Committee has shown it is willing to shake up the sports on its programme, tennis could perhaps do with a headline-making Tokyo 2020.

Murray, the two-time defending men's champion, will target an improbable hat-trick. A hat-trick for the injury-hit former world number one would be a sensation, and Osaka landing gold in the women's tournament would surely be one of the great moments of the Games.

DJOKOVIC FOLLOWING IN THE FOOTSTEPS OF GRAF

When Steffi Graf beat Gabriela Sabatini in the women's singles final at Seoul, it completed what we know now as the calendar 'Golden Slam'. She had already won the Australian Open, French Open, Wimbledon and the US Open, and the feat of the then 19-year-old West German has yet to be repeated.

Now Djokovic is three-fifths of the way to a similar clean sweep of the majors and the Olympics, with the US Open getting under way on August 30 in New York.

He teetered on not going to Tokyo, and perhaps he is to some extent endangering his chances at Flushing Meadows by spending more time travelling and enduring bubble life, while others rest up.

But Djokovic is a fiercely proud Serbian and could not resist a great chance of winning gold for his country. He landed bronze at the 2008 Games in Beijing but in 2012 he lost to Juan Martin del Potro in the bronze-medal match, and a cruel draw at Rio four years later saw him assigned Del Potro in the first round.

Top seed Djokovic bowed out in two tie-breaks to the powerful Argentinian, describing the outcome as "one of the toughest losses in my career".

There is no danger of a hat-trick of defeats to Del Potro, which may help Djokovic. Del Potro has been battling for two years to get back to fitness, undergoing four rounds of right knee surgery in a bid to get back on tour.

RAISING THE BAR AT THE OLYMPICS

How the Olympic village functions in Tokyo will be distinctly different to at previous Games, given the pandemic restrictions in place that could be a real buzzkill.

But in the past there have been countless cases of athletes becoming inspired by their surroundings and going on to perform above their usual level.

It can be a party village, and it can also be an eyebrow-raising experience as global superstars rub shoulders with competitors who might struggle for recognition in their home towns. More than anything, the shared team experience, fighting for a collective cause, can make a middling athlete believe they can be great.

Monica Puig was a massive tennis outsider in 2016 but the then world number 34 won the women's singles, stunning Angelique Kerber in the final after beating Petra Kvitova and Garbine Muguruza en route. That gave Puerto Rico their first ever Olympic gold medal.

In 1992, a tournament that featured the likes of Pete Sampras, Jim Courier, Stefan Edberg and Boris Becker finished with a staggering final match-up of Marc Rosset versus Jordi Arrese, who in his home city of Barcelona was edged out 8-6 in the fifth set by the Swiss world number 43. Nobody would have predicted that head to head for gold.

Similarly, at Athens 2004, Nicolas Massu beat Mardy Fish in the gold medal match of a tournament that featured Federer, Andy Roddick, Carlos Moya and Tim Henman.

In the 1996 Atlanta Games, Lindsay Davenport, who had just turned 20, took inspiration from being the daughter of an Olympian, with dad Wink having played volleyball for the United States at Mexico City in 1968.

Davenport was beginning to make an impact on the WTA Tour but was only the ninth seed at the Olympics, yet she swept through the rounds before sinking Arantxa Sanchez Vicario 7-6 (10-8) 6-2 in the final.

"It's like one of those things I look back on and I'm like, 'Was that me?'," Davenport told The Tennis Podcast last year.

"It doesn't seem like it was real. I'd made the transition to the pro tour pretty well, but I liked hanging out between eight and 16 in the rankings. I was very insecure, unsure of what could I do. I liked doing well but I wasn't sure I wanted to do too well because it seemed really overwhelming to be one of those top players.

"Here I go at 20 years old to Atlanta for two or three weeks, in a setting that seemed so comfortable. Look at all these athletes, you have all different shapes and sizes, you have players that are really working hard but have so much in common and you get to hang out with them, breakfast, lunch, dinner in the village."

Davenport was a future world number one and three-time grand slam singles champion, but at this point in her career being an American at an Olympics in the United States was just a thrill.

"You're sharing this with your team-mates who are some of my best friends in Mary Joe Fernandez, Monica Seles. It was the best time ever," she said.

"By the time the tournament actually started we were like, 'Yeah, I'll go play my match and then we'll go back to the village and we'll hang out', and everything went so fast in those few weeks.

"And there I was left standing, winning at the end because I was so incredibly happy and excited with everything that was going on. I kind of forgot what was my job.

"When it became a reality of even just making the team in '96, it was so huge also for my family with having a second generation Olympian."

Roger Federer is in the draw for the US Open, but it remains unclear whether he will be fit to take part in the final grand slam of the year.

The United States Tennis Association confirmed on Wednesday that Federer was one of six former men's champions to receive direct entry into the draw.

Federer this month withdrew from the Olympic Games, citing a setback with his knee, on which he had two surgeries in 2020.

The Swiss, though, expressed his desire to return the tour, with Flushing Meadows providing his last chance to add to his tally of 20 major titles in 2021.

A five-time winner in New York, Federer has not reached the final at the US Open since 2015.

In the women's singles draw, Naomi Osaka and Serena Williams have each received direct entries into the draw.

Reigning champion Osaka missed Wimbledon having withdrawn from the French Open after the first round to protect her well-being amid a fallout following her decision to not attend post-match media conferences.

Williams is still awaiting a record-tying 24th grand slam title, the 39-year-old forced to retire from her first-round match at Wimbledon because of an injury to her right leg.

Having seen crowds return to a range of tour events, former Wimbledon winner Pat Cash understands the disappointment of tennis moving back to behind closed doors at the Olympic Games in Tokyo.

Each of the three grand slam events to have taken place this year has been held with fans in attendance, with Centre Court seeing capacity crowds for each of the singles finals at Wimbledon. The US Open, which begins on August 30, will allow 100 per cent fan capacity at Flushing Meadows for the final major of 2021.

However, Cash does not believe the lack of spectators at the Games will have too much of an impact on the players who have elected to travel to Japan.

"Well it's unfortunate that the Olympics won't have any fans. I think that's a real disappointment," Cash told Stats Perform.

"But 95 per cent of our life is played on an empty practice court and stadiums.

"Certainly, when you're coming through, nobody's watching you. It's only when you get to Wimbledon or something that you play with crowds, and they can make a difference. We've also been playing most of the year without them.

"To go back [to no fans] it's unfortunate, but it's not something unusual for the players. The crowd certainly does make a difference. It makes a difference with attention and with the crowd roaring and whistling or whatever they want to do."

World number two Naomi Osaka, who will return to action having withdrawn from the French Open to protect her well-being and subsequently skipped Wimbledon, is one athlete who could have benefited from the home support in Japan.

Though he is unsure of how boisterous the home crowd would have been in Tokyo, Cash still feels for the 23-year-old four-time Grand Slam winner.

"With no crowds there that's disappointing for her," he added. 

"But you know, it's sort of something we've become used to on the tour - playing with empty crowds and the nerves still kick in, it is all about winning, and players tend to learn to block the crowds out quite well.

"They stay in their own world when they're on the tennis court. The urgency and the intensity of a match is not really going to change that much because the players really want this for themselves."

Naomi Osaka is less likely to claim Olympics glory on home soil in Tokyo because her lack of match practice will be a disadvantage, according to Pat Cash.

Japan's Osaka has not played since withdrawing from the French Open after one match at the end of May, having revealed she would skip press conferences as "people have no regard for athletes' mental health".

Prior to taking a break from the sport, four-time grand slam champion Osaka revealed she had suffered "long bouts of depression" since winning the US Open in 2018.

The 23-year-old said this month she wants "some level of privacy and empathy" from the media when she returns to action and but also discussed her excitement at playing in a "dream" Olympics.

Former Wimbledon champion Cash insists Osaka has the game to triumph but feels it is a tougher task now given her main opponents are coming off two grand slams in quick succession.

"Yeah, she said [she was taking] time out – it's hard to know if she's going to be match hardened," Cash said to Stats Perform.

"I think that's the thing about playing Wimbledon, the grass court season. Are you match toughened? 

"That goes a huge, huge way [to achieving success, and not having that] is putting yourself under pressure and especially under those circumstances if it's for a gold medal."

Cash feels the quality and depth of opposition in the women's draw is another obstacle in Osaka's bid for gold.

Wimbledon winner Ash Barty, beaten finalist Karolina Pliskova, former French Open champion Iga Swiatek and Aryna Sabalenka are scheduled to be among the highest-ranked competitors for Osaka at the Olympics.

Cash added: "There are a lot of good players too. Going back onto the hard court, I think that favours certain players who hit the ball hard like Sabalenka for instance.

"But there's 30 girls who really do think they can win a gold medal there and I think that's true. 

"So it's very hard to predict who will win, obviously Japan want Osaka to win, but with her being out, I think it's less likely than in a normal circumstance where she's playing matches. 

"But she's such a talent that she really could come out there and blast players away, so I wouldn't put it past her."