The leaders of tennis' four grand slam events have commended Naomi Osaka for opening up about her mental health problems and have vowed to put players' wellbeing first.

Osaka pulled out of the French Open on Monday, a day after organisers fined the four-time grand slam winner and threatened her with more severe sanctions for refusing to attend mandatory media conferences.

The world number two said in a statement posted on social media that she has had "long bouts of depression" since winning the US Open in 2018 and never intended for her stance to become a distraction.

Osaka also indicated that she was willing to work closely with tour officials "to discuss ways we can make things better for the players, press and fans."

Amid criticism for the way in which they have handled the matter, those in charge of the French Open, Wimbledon, US Open and Australian Open have now softened their stance.

A joint statement on Tuesday from French tennis federation president Gilles Moretton, All England Club chairman Ian Hewitt, U.S. Tennis Association president Mike McNulty and Tennis Australia president Jayne Hrdlicka read: "On behalf of the Grand Slams, we wish to offer Naomi Osaka our support and assistance in any way possible as she takes time away from the court.

"She is an exceptional athlete and we look forward to her return as soon as she deems appropriate. Mental health is a very challenging issue, which deserves our utmost attention.

"It is both complex and personal, as what affects one individual does not necessarily affect another. 

"We commend Naomi for sharing in her own words the pressures and anxieties she is feeling and we empathise with the unique pressures tennis players may face. 

"While players' wellbeing has always been a priority to the Grand Slams, our intention, together with the WTA, the ATP and the ITF, is to advance mental health and wellbeing through further actions.

"Together as a community we will continue to improve the player experience at our tournaments, including as it relates to media.

"Change should come through the lens of maintaining a fair playing field, regardless of ranking or status. Sport requires rules and regulations to ensure that no player has an unfair advantage over another.

"We intend to work alongside the players, the tours, the media and the broader tennis community to create meaningful improvements. As Grand Slams, we aim to create the stage for the players to achieve the highest accolades in our sport."

Osaka's shock withdrawal generated an outpouring of support across the tennis world and beyond, with the likes of Serena Williams, Billie Jean King and Martina Navratilova backing the 23-year-old's stance.

Gael Monfils also chipped in on Tuesday, the top-ranked French men's player pointing out that it is difficult to judge Osaka's situation from the outside.

"We need Naomi. We need her definitely to be 100 per cent," he said following his win over Albert Ramos-Vinolas.

"We need her back on the court, back on the press conference, and back happy. You know, that's what we need.

"What she's dealing with is tough for me to even judge, because I think she has massive pressure from many things.

"I think she's quite young. She's handling it quite well. Sometimes we want maybe too much from her, and then how she says maybe she can't manage it that well, so sometimes for sure she's going to make some mistakes.

"But I give her always the chance because she's a champion, she's quite young, she has a huge influence. I think she needs to take some time for herself to work on herself, feel better."

Boris Becker fears Naomi Osaka's career could be "in danger" after she withdrew from the French Open to prioritise improving her mental health.

Osaka had hit the headlines by revealing she would not face the media at Roland Garros because "people have no regard for athletes' mental health" during news conferences.

The four-time grand slam champion was fined for not fulfilling her media duties after beating Maria Tig and warned she could face more severe sanctions.

Osaka on Monday revealed she had pulled out of the second major of the year to take time away from the court, having struggled with "long bouts of depression" since winning the US Open in 2018.

The 23-year-old also spoke of her struggles with social anxiety and Becker is concerned for her tennis future.

Becker, a winner of six grand slam titles in his illustrious career, told Eurosport: "I heard her first response a couple of days ago about this media boycott and that is something to be always taken seriously, especially from such a young woman.

"She couldn't cope with the pressures of facing the media after she loses a match, but that happens frequently and you have to deal with it.

"I always believed the media was part of the job. Without the media, there is no prize money, no contracts, you don't get half the cake. I hated the media and I didn't like talking to journalists, but you had to do it.

"Now she is pulling out of the tournament altogether because she can't cope with it and that raises much bigger questions for me.

"If she can't cope with the media in Paris, she can't cope with the media in Wimbledon or the US Open. So I almost feel like her career is in danger due to mental health issues."

Naomi Osaka's shock withdrawal from the French Open generated an outpouring of support across the tennis world and beyond. 

The four-time grand slam winner pulled out of Roland Garros on Monday, a day after tournament organisers said her continued refusal to attend mandatory press conferences could result in her being thrown out of the event.

Osaka said in a statement posted to social media that she has had bouts of depression since winning the US Open in 2018 and never intended for her stance to become a distraction. 

Monday's action in Paris had mostly been completed when the news broke, but Serena Williams shared her thoughts following an evening match. 

Williams acknowledged feeling anxious dealing with the press at times early in her career, but said she believed the experience made her stronger. 

Top of mind, however, was concern for Osaka. 

"The only thing I feel is that I feel for Naomi. I feel like I wish I could give her a hug because I know what it's like," Williams said.

"We have different personalities, and people are different. Not everyone is the same. Everyone is different and everyone handles things differently.

"You just have to let her handle it the way she wants to, in the best way she thinks she can, and that's the only thing I can say. I think she's doing the best that she can."

Osaka's fellow players and others took to social media with encouraging messages for the 23-year-old. 

Venus Williams wrote on Instagram: "So proud of you. Take care of yourself and see you back winning soon!"

Young American star Coco Gauff responded to Osaka's tweet by writing "stay strong ... I admire your vulnerability." 

A pair of tennis legends also weighed in on Twitter. 

"I am so sad about Naomi Osaka. I truly hope she will be ok," Martina Navratilova wrote.

"As athletes we are taught to take care of our body, and perhaps the mental and emotional aspect gets short shrift.

"This is about more than doing or not doing a press conference. Good luck Naomi - we are all pulling for you!"

Billie Jean King added: "It’s incredibly brave that Naomi Osaka has revealed her truth about her struggle with depression. Right now, the important thing is that we give her the space and time she needs. We wish her well."

Mardy Fish, the former ATP player who reached number seven in the world, wrote to Osaka: "Mental health is nothing to criticise. Nothing to joke about. Pls [sic] take your mental health seriously. Without my support system, I truly believe I would not be here today. Here for you."

That public show of support extended beyond tennis, as prominent NFL and NBA players praised Osaka for her courage. 

"We are with you," said Seattle Seahawks quarterback Russell Wilson.

NBA star Stephen Curry wrote: "You shouldn't ever have to make a decison like this - but so damn impressive taking the high road when the powers that be don't protect their own. Major respect."

Naomi Osaka pulled out of the French Open on Monday, saying it was "the best thing for the tournament, the other players and my well-being".

The dramatic development comes in the wake of Japan's world number two declaring she would not fulfil press conference duties during the tournament at Roland Garros.

She cited mental health concerns for reaching that decision, and Osaka now says she plans a break from tennis, which may mean she does not play at Wimbledon.

In her withdrawal announcement, Osaka said she has suffered "long bouts of depression" since winning the US Open in 2018.

Grand slam chiefs surprisingly escalated the situation on Sunday by declaring that repeated violations of their code of conduct could see Osaka thrown out of the event.

Now Osaka has taken the matter into her own hands, a day after winning her first-round match.

She wrote on Twitter: "Hey everyone, this isn't a situation I ever imagined or intended when I posted a few days ago. I think now the best thing for the tournament, the other players and my well-being is that I withdraw so that everyone can get back to focusing on the tennis going on in Paris.

"I never wanted to be a distraction and I accept that my timing was not ideal and my message could have been clearer.

"More importantly I would never trivialise mental health or use the term lightly.

"The truth is that I have suffered long bouts of depression since the US Open in 2018 and I have had a really hard time coping with that."

Naomi Osaka's decision to boycott mandatory media interviews at the French Open has left tennis legend Billie Jean King "torn".

Osaka revealed in the build-up to the second grand slam of the year that she would not partake in media duties, stating that "people have no regard for athletes' mental health" during news conferences.

The WTA – organisers of the women's tour – encouraged the Japanese superstar to reach out for support with her mental well-being but stressed she had a "responsibility" to her sport to honour contractual commitments.

The 23-year-old conducted an on-court interview after beating Patricia Maria Tig on Sunday but did not appear at the allotted time for her post-match media conference and was hit with a $15,000 by tournament organisers, who threatened further sanctions, including a possible suspension.

King, a 12-time grand slam singles champion, took to Twitter to outline her stance on what is proving to be a contentious issue.

"I fully admire and respect what Naomi is doing with her platform, so I am a little torn as I try to learn from both sides of the situation," wrote King, a co-founder of the WTA.

"While it's important that everyone has the right to speak their truth, I have always believed that as professional athletes we have a responsibility to make ourselves available to the media.

"In our day, without the press, nobody would have known who we are or what we thought. There is no question they helped build and grow our sport to what it is today.

"I acknowledge things are very different now with social media and everyone having an immediate ability to speak their truth.

"The media still play an important role in telling our story. There is no question that the media needs to respect certain boundaries.

"But at the end of the day it is important that we respect each other and we are in this together."

Osaka plays Ana Bogdan in round two on Wednesday.

Naomi Osaka fended off Patricia Maria Tig at the French Open on Sunday, but the world number two admits she has plenty of room for improvement on clay.

Osaka has been at the centre of attention in the build-up to the tournament, with the 23-year-old refusing to attend mandatory news conferences and suggesting they were not beneficial to her mental health.

The second seed stood by her decision following a straight-sets win over Romanian Tig and was subsequently handed a $15,000 fine and warned repeat offences could see her thrown out of the competition.

However, Osaka did speak in an on-court interview after her 6-4 7-6 (7-4) victory on Court Philippe-Chatrier– just her second win of the season on clay.

"I'd say it’s a work on progress," four-time grand slam winner Osaka said when asked about her clay-court game.

"Hopefully, the more I play the better it'll get. I'm really glad that I won, it's a very beautiful court. I've only played two matches here – one before the roof [was installed] and one right now. Hopefully I'll keep it going."

Next up for reigning US and Australian Open champion Osaka is Ana Bogdan, who defeated Elisabetta Cocciaretto 6-1 6-3.

ANOTHER FRENCH OPEN DUCK FOR KERBER

While Osaka took a place in round two, former world number one Angelique Kerber had no such luck as she came unstuck in the first round at Roland Garros for a third year running.

Now ranked at 27th in the world by the WTA, Kerber lost 6-2 6-4 to qualifier Anhelina Kalinina.

The French Open title has so far eluded Kerber, who has won every other grand slam, and the 33-year-old German has not won a match in Paris since 2018, when she reached the quarter-finals, having also made the last eight in 2012.

Indeed, the 33-year-old's run to the quarters in 2018 was the only time in her last six appearances at Roland Garros that she has progressed beyond the first round.

"She started well and had nothing to lose, while it took me too long to get into the contest," Kerber said. "I will try to learn from the match now because I played good the last few weeks and I had good matches."

SABALENKA AND KVITOVA BATTLE THROUGH

Aryna Sabalenka was the other top seed in action on Sunday, though she was made to work for a 6-4 6-3 defeat of Ana Konjuh.

The third seed, who is in the hunt for a first grand slam title having already won the Madrid Open this month, made a sluggish start and two breaks of serve had her 4-2 down to world number 144 Konjuh.

But Sabalenka rallied herself and a streak of four straight games handed her the set, and a further three successive breaks to start the second put her in command.

Konjuh managed to save the first match point, only for the Croatian qualifier to hit the net as Sabalenka progressed at the second time of asking.

Petra Kvitova, the 11th seed, needed three sets to overcome Greet Minnen 6-7 (3-7) 7-6 (7-5) 6-1, and had to save a match point in the process.

Two-time Wimbledon champion Kvitova was on the edge of a shock exit at 6-5 and a break down in the second set, but a backhand winner rescued her from the brink and forced another tie-break, which the Czech won before carrying the momentum into the decider.

"I would say that from my side it wasn't really good from the beginning," said Kvitova, a semi-finalist at Roland Garros last year.

"I was struggling, I was missing a lot, I was double-faulting a lot.

"I didn't really feel myself that well. I was pretty tight, it was really tough. I mean, I was fighting not only with her but with myself as well. I'm glad that in the end I beat myself as well and beat her, so that counts."

Kvitova will next face Elena Vesnina, who beat lucky loser Olga Govortsova 6-1 6-0 to seal a first singles win since she became a mother in 2018 and took a two-year break from tennis.

Naomi Osaka has been fined and threatened with possible expulsion from the French Open after choosing not to take part in mandatory media interviews at the tournament.

Osaka declared her intentions in the build-up to the second grand slam of the year, stating that "people have no regard for athletes' mental health" during news conferences.

The WTA – organisers of the women's tour – encouraged the Japanese superstar to reach out for support with her mental well-being but stressed she had a "responsibility" to her sport to honour contractual commitments.

The 23-year-old conducted an on-court interview after beating Patricia Maria Tig on Sunday but did not appear at the allotted time for her post-match media conference.

Tournament organisers have fined Osaka $15,000 for breaching their code of conduct and warned she could be defaulted from the French Open – and face possible suspensions from other majors – should she continue a media blackout.

Osaka, holder of the US Open and Australian Open titles, has previously said any such fines should go towards a mental health charity.

A statement on the French Open's official website read: "Naomi Osaka announced last Wednesday on social media that she would not participate in the mandatory media interviews at Roland Garros 2021.

"Following this announcement, the Roland Garros teams asked her to reconsider her position and tried unsuccessfully to speak with her to check on her well-being, understand the specifics of her issue and what might be done to address it on site.

"Following the lack of engagement by Naomi Osaka, the Australian Open, Roland Garros, Wimbledon and the US Open jointly wrote to her to check on her well-being and offer support, underline their commitment to all athletes' well-being and suggest dialogue on the issues. She was also reminded of her obligations, the consequences of not meeting them and that rules should equally apply to all players.

"Naomi Osaka today chose not to honour her contractual media obligations. The Roland Garros referee has therefore issued her a $15,000 fine, in keeping with article III H. of the code of conduct."

The statement went on to say: "We have advised Naomi Osaka that should she continue to ignore her media obligations during the tournament, she would be exposing herself to possible further code of conduct infringement consequences.

"As might be expected, repeat violations attract tougher sanctions including default from the tournament and the trigger of a major offence investigation that could lead to more substantial fines and future grand slam suspensions.

"We want to underline that rules are in place to ensure all players are treated exactly the same, no matter their stature, beliefs or achievement.

"As a sport there is nothing more important than ensuring no player has an unfair advantage over another, which unfortunately is the case in this situation if one player refuses to dedicate time to participate in media commitments while the others all honour their commitments."

The statement was co-signed by organisers from all four grand slams.

Naomi Osaka kicked off her bid for a maiden French Open title with a battling straight-sets win over Patricia Maria Tig on day one at Roland Garros.

The second seed, who has failed to get beyond the third round in four previous attempts, won 89 per cent of her first serve points on her way to seeing off Tig 6-4 7-6 (7-4) in a time of one hour and 48 minutes.

She had 39 winners to 35 unforced errors and will now take on Ana Bogdan – a 6-1 6-3 winner against Elisabetta Cocciaretto on Sunday – for a place in the last 32.

Osaka, who announced before the tournament that she would not be doing post-match media duties, had just one clay-court victory to her name heading into the second grand slam of the year, but she soon found her groove against world number 63 Tig.

However, after earning an early break of serve, the Australian Open champion squandered three set points in the eighth game as Tig hit back.

Osaka made her superiority show in the following game to take a 1-0 lead in the match and held throughout a tight second set, which went the distance.

Tig, who reached the third round in Paris last year, initially held her own but Osaka pulled away to take the tie-break 7-4 on Court Philippe-Chatrier.

Data Slam: Osaka seeking more major glory

World number two Osaka has now won her last 15 matches at grand slams and, even accounting for her record on clay, she will take some stopping in Paris. 

WINNERS/UNFORCED ERRORS
Osaka – 39/35
Tig – 19/21

ACES/DOUBLE FAULTS
Osaka – 1/3
Tig – 4/5

BREAK POINTS WON
Osaka – 2/10
Tig – 1/2

The WTA says Naomi Osaka has a "responsibility" to her sport to speak to the media after the world number two opted to snub the press at the French Open.

Japanese sensation Osaka this week stated she would not face the media at Roland Garros as "people have no regard for athletes' mental health" during press conferences.

The WTA on Friday stated that it would welcome dialogue with Osaka over possible approaches to support players, but the organisation says the four-time grand slam winner should speak to journalists.

"Mental health is of the utmost importance to the WTA and for that matter, every individual person. We have a team of professionals and a support system in place that look after our athletes' mental and emotional health and well-being," a WTA statement said.

"The WTA welcomes a dialogue with Naomi (and all players) to discuss possible approaches that can help support an athlete as they manage any concerns related to mental health, while also allowing us to deliver upon our responsibilities to the fans and public. 

"Professional athletes have a responsibility to their sport and their fans to speak to the media surrounding their competition, allowing them the opportunity to share their perspective and tell their story."

Osaka said she wants fines she will be hit with for her media snub in Paris to go to a mental health charity.

She explained in a social media post on Wednesday: "I'm writing this to say I'm not going to do any press during Roland Garros.

"I've often felt that people have no regard for athletes' mental health, and this rings true whenever I see a press conference or partake in one."

 May 26, 2021

Osaka added: "We're often sat there and asked questions that we've been asked multiple times before, and I'm just not going to subject myself to people that doubt me."

World number one Ash Barty told the media when asked about Osaka's stance on Friday: "We know what we sign up for as professional tennis players. I can't really comment on what Naomi is feeling or her decisions she makes.

"At times press conference are hard of course but it's also not something that bothers me. Certainly doesn't keep me up at night what I say and hear or what you guys ask me."

Defending champion Iga Swiatek said: "I don't find it difficult. It gives us a chance to explain our perspective, so I think it's good."

Gilles Moretton, the president of the French Tennis Federation (FFT), said Osaka is making a "phenomenal mistake".

He told L'Equipe: "It's a deep regret, for you journalists, for her [Osaka] personally and for tennis in general. I think this is a phenomenal mistake."

Moretton added that Osaka ignoring the media is a "very detrimental to sport, tennis and probably to her."

Naomi Osaka has imposed a media ban during her upcoming French Open campaign, citing mental health reasons.

Osaka – the reigning Australian Open champion and four-time grand slam winner – announced the shock media boycott ahead of the Roland Garros event, which will get underway on Sunday.

Under French Open rules, typical of any tennis tournament, players are required to hold media conferences after each match.

Osaka is the world's highest earning female athlete and will be fined by tournament officials should the world number two follow through and not take part in news conferences.

Japanese star Osaka hopes the fines she will receive can be donated towards mental health charity.

"I'm writing this to say that I'm not going to do any press during Roland Garros," Osaka wrote on Twitter. "I've often felt that people have no regard for athletes' mental health and this rings true whenever I see a press conference or partake in one.

"We're often sat there and asked questions that we've been asked multiple times before or asked questions that bring doubt into our minds and I am not going to subject myself to people who doubt me.

"I've watched many clips of athletes breaking down after a loss in the press room and I know you have as well. I believe that whole situation is kicking a person while they're down and I don't understand the reasoning behind it.

"Me not doing press is nothing personal to the tournament … However, if the organisations think that they can just keep saying, 'do press or you're gonna be fined', and continue to ignore the mental health of the athletes that are centrepiece of their co-operation then I just gotta laugh."

Osaka heads to Paris having never progressed beyond the third round of the French Open.

The 23-year-old skipped last year's French Open amid the coronavirus pandemic, though she claimed her second US Open crown at Flushing Meadows.

Simona Halep suffered a worrying leg injury just over two weeks out from the French Open at the Internazionali BNL d'Italia, where Serena Williams and Naomi Osaka crashed out.

Halep, the 2018 French Open champion, had dominated the first set against Angelique Kerber, winning 6-1, but came off the court with an apparent calf problem with the scores level at 3-3 in the second.

She received treatment but an emotional Halep was forced to withdraw from the clash, the defending champion handing victory to Kerber.

The Romanian was then helped from the grandstand court, leaving the area with strapping on her leg and a heavy limp, raising doubts about her ability to compete at Roland Garros, where she would likely be one of the favourites.

Earlier Williams made her first appearance on the tour since February, losing the 1,000th match of her glittering career to Nadia Podoroska, who reached the semi-finals in Paris last year.

Podoroska prevailed 7-6 (8-6) 7-5, with 23-time grand slam champion Williams not too downhearted by a defeat to an accomplished clay-court player.

"It's tough to have a first match on clay. It was definitely kind of good to go the distance and to try to be out there, but clearly I can do legions better," Williams said. 

"She has a good game, for sure, obviously. She's very consistent. Overall, it was good for me to play such a clay-court player on clay today, but it's a little frustrating. But it's all right. It is what it is.

"I have been training for months, but it feels definitely different on clay to make that last adjustment. Just filling out the game, finding the rhythm. Even sliding and confidence with that, with movement. That's always like a little struggle in the first two matches, and then I'm raring to go."

Osaka has yet to find her footing on clay and the reigning Australian Open champion came up short in the second round as she suffered a surprise loss to Jessica Pegula.

Pegula said after her 7-6 (7-2) 6-2 win: "I know she doesn't love clay, so I just tried to be the clay court player out there today, and it worked just good enough."

World number one Ashleigh Barty had no such difficulties in her 6-4 6-1 over Yaroslava Shvedova, but fourth seed Sofia Kenin was a shock loser to Barbora Krejcikova.

Petra Kvitova was beaten in three sets by Vera Zvonareva but Madrid champion Aryna Sabalenka, last year's French Open champion Iga Swiatek, Elina Svitolina, Karolina Pliskova and Garbine Muguruza all progressed while teenager Coco Gauff knocked out 17th seed Maria Sakkari.

Serena Williams made an unsuccessful return to the WTA Tour as she joined Naomi Osaka in crashing out of the Internazionali BNL d'Italia in the second round on Wednesday.

Williams was playing the 1,000th match of her glittering career against Nadia Podoroska, her first since losing in the Australian Open semi-finals to Osaka in February.

The American has experienced significant success in Rome, winning the title four times, but was always likely to be tested by a player who reached the French Open semi-finals last year.

And that proved the case as she slumped to a 7-6 (8-6) 7-5 defeat despite threatening a second set fightback.

Having won the first set on a tie-break, Podoroska continued to dominate the longer exchanges and went 5-2 up in the second.

From there, Williams won 12 straight points to level matters at 5-5, but Podoroska then claimed a nervy service hold to force the 23-time grand slam champion to serve to stay in the match.

She never came close to doing so as Williams was broken to love, a miscued forehand long giving Podoroska one of the biggest wins of her career.

Earlier in the day, Osaka was defeated in straight sets by Jessica Pegula.

Osaka has made no secret of her discomfort on clay, having never gone beyond the third round at Roland Garros.

All of her 10 WTA singles titles have come on the hard court and she was undone on the red dirt once more as Pegula prevailed 7-6 (7-2) 6-2.

Rafael Nadal and Naomi Osaka have earned the top 2021 prizes at the Laureus World Sports Awards, while Patrick Mahomes, Lewis Hamilton and Mohamed Salah were all also recognised.

Tennis dominated the individual honours as Nadal collected a fourth award, named Laureus World Sportsman of the Year for the second time.

The Spaniard, who has also previously taken the 2006 Breakthrough Award and the 2014 Comeback Award, was selected after winning the French Open to tie Roger Federer's record of 20 grand slam titles.

Nadal, who said he "can't be happier", added: "Winning the French Open and equalling the 20th grand slam of Roger Federer has been an unforgettable moment.

"It means a lot to equal my great rival, but at the same time, my great friend. It's something very special after all the history we have had together on and off court."

Laureus World Sportswoman of the Year Osaka, the 2019 Breakthrough winner, claimed a second US Open triumph while supporting the 'Black Lives Matter' movement.

"I think it is important to use my voice, because, for me, I feel like I often hold back a lot and worry about what people think of me, but you know if you have a platform it is very important you use it," the Japanese superstar said.

Kansas City Chiefs quarterback Mahomes won the Super Bowl last year and played in the big game again earlier in 2021, making him the latest Laureus World Breakthrough of the Year Award winner.

He and Formula One great Hamilton both joined Osaka in demonstrations against racial inequality.

Two-time Laureus winner Hamilton got his hands on the Athlete Advocate of the Year Award and said: "This past year has been incredibly difficult for so many, but it has also been heartening to see the power of our collective voices spark new conversations and change.

"The impact of each and every one of you who have stood up, is so inspiring, so I want to thank you. Please keep fighting, keep shining your light."

Liverpool's Salah supported a number of causes and led the Reds to Premier League glory, receiving the Laureus Sporting Inspiration Award, but Bayern Munich of the Bundesliga were the World Team of the Year for the second time.

Nadal and Osaka were not the only tennis stars to have their name called, as Billie Jean King took the Laureus Lifetime Achievement Award.

Naomi Osaka suffered a shock second-round exit to Karolina Muchova at the Madrid Open, but there was no such trouble for Simona Halep as she held off Zheng Saisai.

Second seed Osaka was playing just her second match on clay since the 2019 French Open due to injury issues and became the latest big name to fall at the hands of Muchova.

The world number 20, who had already defeated two top-five players this season, prevailed 6-4 3-6 6-1 in a time of one hour and 49 minutes in the Spanish capital.

Osaka has now lost two of her last three matches, having been eliminated from the Miami Open quarter-finals by Maria Sakkari at the end of March.

"I think today for me it was quite different from the last time I lost in Miami, and I actually think I played much better here, so I'm very happy about that," Osaka said.

"I think what I can take away from this is that I tried my best throughout the entire match. I think tennis-wise, I felt I was too defensive in the first set.

"I wouldn't say I’m happy that I lost, but I think I learned a lot. So that's all I can hope for."

Two-time champion Halep has yet to drop a set in this year's tournament after seeing off unseeded opponent Zheng 6-0 6-4.

Halep took nine games in a row at the start of the match but, like in her opening-round win over Sara Sorribes Tormo, she had to hold off a late surge from her opponent to advance.

Next up for Halep is a last-16 showdown with Elise Mertens, who beat Elena Rybakina 7-6 (7-4) 7-5 in the last of Sunday's matches.

Fifth seed Aryna Sabalenka safely advanced earlier in the day thanks to a 6-3 6-3 win against Daria Kasatkina, while Sakkari beat Anett Kontaveit 6-3 6-1.

Sabalenka was on course to face Victoria Azarenka for a place in the quarter-finals, but the Belarussian withdrew from her match with Jessica Pegula because of a back injury.

Elsewhere, Jennifer Brady, who knocked out fellow American Venus Williams in the first round, eased past Jelena Ostapenko 6-2 6-1.

Brady faces a tricky test in the next round with Anastasia Pavlyuchenkova, who defeated sixth seed Karolina Pliskova 6-0 7-5, seeking another scalp.

Naomi Osaka quickly adapted to playing again on clay as she was among the seeds to triumph in Friday's action at the Madrid Open.

Osaka had not featured on the red dirt since a third-round exit at the 2019 French Open, missing out on competing on the surface last year due to injury.

This year's Australian Open champion stumbled out of the blocks against Misaki Doi, quickly falling 3-0 behind in the opener, but recovered from the early setback to prevail in straight sets.

The second seed hit 26 winners in a 7-5 6-2 triumph over her compatriot, who has now lost all three of their meetings on the WTA Tour.

"You obviously want to play well against a player that's from the same country," Osaka said.

"I never really know what to expect because I feel like she always plays better when I play against her, so it's a bit tough to manage controlling my emotions. But I think I was able to do it pretty well."

Simona Halep also won in her opener at the event, the third seed racing through the first set before holding off a fightback from Sara Sorribes Tormo in the second.

Halep – who needed 83 minutes to clinch a 6-0 7-5 victory – has been crowned champion twice in Madrid, the first time coming in 2016 before she returned a year later to successfully defend the title.

Aryna Sabalenka wasted little time in seeing off the challenge of Vera Zvonareva, the fifth seed producing 37 winners in a 6-1 6-2 win, her first ever in the event.

Maria Sakkari found the going much tougher before eventually ousting Amanda Anisimova, losing the first seven games in a row before rallying for a 0-6 6-1 6-4 triumph.

Daria Kasatkina was also pushed in her opener, with a 4-6 6-4 7-6 (7-1) win over Irina-Camelia Begu taking just over three hours.

Karolina Pliskova had to go the distance after falling a set behind against Coco Gauff, while two-time finalist Victoria Azarenka came out on top in a deciding set against Ekaterina Alexandrova.

In the final match on a busy day, Jennifer Brady won 6-2 6-4 in an all-American clash with Venus Williams.