Top seed Ashleigh Barty moved into the quarter-finals with a three-set win over Shelby Rogers while Petra Kvitova and Garbine Muguruza exited in the Round of 16 of the Volvo Car Open in Charleston.

World number one Barty was pushed all the way by 52nd ranked Rogers, with both players trading breaks in the final set, before the Australian prevailed 7-6 (7-3) 4-6 6-4.

The victory extends Barty's winning streak to eight matches having won last week's Miami Open.

Barty won 82 per cent of first serve points and sent down 10 aces to get the edge on the American, who saved eight of 13 break points throughout the match.

"The conditions are difficult. It's pretty quick," Barty said in her on-court interview post-game.

"Shelby was able to control the centre of court for a lot of the match. It was about trying to get control when I could. She's an exceptional player, it's always a fight no matter what surface or where we are in the world. It's always one that I enjoy."

Barty will play Spaniard 71st ranked Paula Badosa in the quarter-finals after she beat Caty McNally 6-3 6-3.

Third seed Kvitova was the major casualty on Thursday, losing 6-4 6-1 to Montenegrin Danka Kovinic.

The first set was tightly fought before Kovinic pulled away as Kvitova's errors mounted.

"We both have pretty big serves and she's very good hitting from the baseline," Kovinic said post-game. "Today it was the key that I tried, and did it really well, to take her pace of the ball and use her energy."

Sixth seed Garbine Muguruza also bowed out injured, despite leading 6-0 2-2 against 11th seed Yulia Putintseva.

Muguruza laboured for a few games after a medical time-out before retiring with a left leg injury. Putintseva will next face Kovinic.

Seeds Ons Jabeur, Veronika Kudermetova and Cori Gauff also progressed to the last eight, while Sloane Stephens won in straight sets against Ajla Tomljanovic.

Meanwhile at the Copa Colsanitas second round in Bogota, seventh seed Tereza Martincova was knocked out, going down 6-3 6-3 to Colombian teenager Maria Osorio Serrano.

On the outdoor clay courts, fifth Tamara Zidansek moved into the quarter-finals with a 6-2 6-3 win over Giulia Gatto-Monticone, while Harmony Tan beat Daniela Seguel.

Garbine Muguruza continued her superb start to 2021 as the former world number one won a WTA Tour-leading 21st match of the season to progress at the Volvo Car Open.

Muguruza – the sixth seed in Charleston – dispatched qualifier Magdalena Frech 6-1 6-3 in her first match of the clay court season on Tuesday.

Two-time grand slam champion Muguruza has already reached three finals this year, winning once in Dubai, and took just 70 minutes to overcome Fech on her return to Charleston following an eight-year absence. 

"I'm happy that I got this win, that I fought hard, that I kept my fighting spirit through the whole match, also in the second set which was tighter than the first set," Muguruza told reporters, in quotes reported on the WTA's official website.

Joining Muguruza in the round of 16 is third seed and fellow former grand slam champion Petra Kvitova, who saw off Storm Sanders 7-6 (7-4) 6-2 in her first-ever match at the WTA Premier tournament. 

Meanwhile, two former Charleston champions will go head-to-head after Sloane Stephens – a winner in 2016 – beat lucky loser Xinyu Wang 6-2 6-4 to tee up a second-round tie with 2019 victor Madison Keys.

Shelby Rogers took advantage of being in familiar surroundings by seeing off Kristina Mladenovic, while Monterrey Open champion Leylah Fernandez also progressed at the expense of 16th seed Shuai Zhang.

As for American sensation Coco Gauff, the 14th seed beat Tsvetana Pironkova 6-3 6-0 en route to the last 32.

There was a first-round surprise at the Colsanitas Cup in Bogota, where second seed Sara Sorribes Tormo was upstaged by 2012 French Open runner-up Sara Errani 7-5 7-5.

Colombian youngster Maria Camila Osorio got the better of American Sachia Vickery 6-3 6-2, with a potential top-100 scalp of Tereza Martincova next in her sights.

World number two Naomi Osaka and defending champion Ash Barty advanced to the quarter-finals of the Miami Open.

Osaka reached the last eight at the WTA Premier event for the first time in her career thanks to Monday's straight-sets win over Elise Mertens.

World number one Barty overcame two-time grand slam champion Victoria Azarenka in a tough three-set battle in Miami.

THERE'S NO STOPPING OSAKA

Australian Open champion Osaka extended her winning streak to a remarkable 23 matches.

Osaka defeated 16th seed Mertens 6-3 6-3 to stay hot – Venus Williams, Serena Williams, Justine Henin and Azarenka are the only other players with winning streaks of 23 or more matches since 2000.

"It definitely feels very special," four-time major winner Osaka said. "This is one of my favourite tournaments to play, and of course I'm sad I hadn't been able to get to the second week the last times that I have played this tournament. But I'm here now, and hopefully it will go well this time."

Maria Sakkari is next for Osaka after the 23rd seed saved six match points in her 6-4 2-6 7-6 (8-6) win over Jessica Pegula.

BARTY WINS BATTLE OF PAST AND PRESENT NUMBER ONES

In a rollercoaster battle, top seed Barty prevailed 6-1 1-6 6-2 against 14th seed Azarenka.

Barty extended her winning streak in Miami to nine matches after coming out on top against the former world number one.

"Playing against Vika you have to be ready right from the first point," Barty said. "I felt like I did that well in the first set and she gave me a few cheap errors. Then through the second she lifted her intensity.

"I probably wasn't sharp enough in those first couple of games to be able to go with her, particularly with new balls. When Vika is ahead and she's a front runner, she's the very best in the world."

Aryna Sabalenka stands in the way of Barty and the semi-finals after the seventh seed trounced Marketa Vondrousova 6-1 6-2.

SVITOLINA WINS THRILLER, ANDREESCU RALLIES

Fifth seed Elina Svitolina rallied past two-time Wimbledon winner Petra Kvitova 2-6 7-5 7-5.

Svitolina made a slow start against the red-hot ninth seed, but the 2018 WTA Finals champion finished strongly to progress.

Anastasija Sevastova took down Ana Konjuh 6-1 7-5 to set up a clash with Svitolina.

Meanwhile, eighth seed and 2019 US Open champion Bianca Andreescu came from behind to defeat two-time slam winner Garbine Muguruza 3-6 6-3 6-2.

Naomi Osaka did not raise a sweat en route to the Miami Open last 16 as Garbine Muguruza moved through but Sofia Kenin and Karolina Pliskova bowed out.

Australian Open champion and second seed Osaka benefited from a walkover after qualifier Nina Stojanovic withdrew ahead of Sunday's clash due to a right thigh injury.

Elise Mertens will face Osaka following the 16th seed's 6-2 0-6 6-2 win against Anett Kontaveit.

Two-time grand slam winner Muguruza rallied past Russian wildcard Anna Kalinskaya at the WTA Premier event.

However, fourth seed Kenin was sent packing as sixth seed Pliskova was tamed by nemesis Jessica Pegula in Miami.

MUGURUZA STAYS HOT

Spanish star Muguruza dug deep to earn her tour-leading 20th win of the season.

Former world number one Muguruza – the 12th seed – prevailed 4-6 6-3 6-4 against Kalinskaya, having trailed 3-0 in the final set.

"I brought my fighting spirit and I could match the level of fighting against Anna, and very happy to go through these tough matches," Muguruza said following two hours, 41 minutes on court.

"Doesn't matter if you play pretty or you play ugly, but you stay strong and you go through these rounds. That gives me an opportunity to feel better and to have another chance."

Muguruza – who has the most final appearances this season with three, having won the Dubai Tennis Championships and finished runner-up at the Qatar Open and Yarra Valley Classic – will next face eighth seed Bianca Andreescu.

Former US Open champion Andreescu overcame fellow seed Amanda Anisimova 7-6 (7-4) 6-7 (2-7) 6-4.

KENIN'S WOES CONTINUE

It has been a rough 2021 for American star Kenin.

Stunned in the second round of the Australian Open – in her title defence – Kenin then crashed out of the Phillip Island Trophy at the first hurdle.

Kenin rallied to beat Andrea Petkovic first-up in Miami, but the 22-year-old was beaten 6-4 4-6 6-4 by 27th seed Ons Jabeur.

Jabeur and Sara Sorribes Tormo – who shocked 21st seed Elena Rybakina 6-1 3-6 6-2 – will meet for a spot in the quarter-finals.

PLISKOVA FALLS TO PEGULA… AGAIN

For the third time this past month, 2019 Miami Open runner-up Pliskova went down 6-1 4-6 6-4 to 29th seed Pegula.

Australian Open quarter-finalist Pegula conquered Pliskova in Doha and Dubai before repeating the feat in Miami on Sunday.

"I played her a lot the last three weeks, three tournaments," Pegula said. "I kind of expected her to play well there. Even when I was up I still felt like she could easily come back just because she plays so aggressive and she serves well."

After reeling off the final four games, Pegula set up a last-16 showdown with 23rd seed Maria Sakkari, who dismantled qualifier Liudmila Samsonova 6-0 6-1.

Garbine Muguruza landed her first title in almost two years with victory over Barbora Krejcikova in Saturday's Dubai Tennis Championships final.

The former French Open and Wimbledon champion has produced some of the best tennis on tour this year but had gone without a trophy to back that up.

However, she put that right with a 7-6 (8-6) 6-3 victory over surprise finalist Krejcikova, a doubles specialist who has never ranked inside the top 50 in singles.

Coach Conchita Martinez has been absent from Muguruza's recent matches after testing positive for COVID-19, keeping tabs with mobile phone footage from courtside.

"She got the virus and was so upset she couldn't come, so this one is for her," Muguruza said.

Muguruza's most recent title had come at the 2019 Monterrey Open, where she successfully defended her title.

She was runner-up at the Australian Open in 2020 and in the early stages of this season made it through to finals at the Yarra Valley Classic and the Qatar Open.

She was beaten by Ash Barty in the first of those, in February, and by Petra Kvitova in Doha last weekend, but Muguruza made sure she did not spurn her latest chance to lift a trophy.

Krejcikova had bizarrely taken a medical break before the match began, seeking treatment on a thumb injury, but that did not prevent her being competitive.

The gruelling first set contained two breaks of serve for each player, and the second was also tightly contested before Muguruza took the title on her second championship point when her opponent went long with a forehand.

Muguruza said on Amazon Prime: "It's a great achievement. I've been coming here for many years and felt I was close but not enough.

"Finally today I got the champion's trophy and I'm very happy after losing a few finals in a row to get this one.

"I feel the consistency is hard to get, but being able to play three finals is a great sign that we are on the right way."

Garbine Muguruza reached the final of the Dubai Tennis Championships after a gruelling victory over Elise Mertens on Friday.

The Spaniard saw six match points come and go in a battle lasting two hours and seven minutes before eventually closing out a 6-4 7-6 (7-5) win.

Having reached the final in Doha last week, where she lost to Petra Kvitova, Muguruza is the fifth player this century to reach back-to-back finals in the Middle East double, after Martina Hingis, Justine Henin, Caroline Wozniacki and Svetlana Kuznetsova.

The two-time major winner has now reached three finals in her past four tournaments and has won 17 matches in 2021.

Despite being ahead for much of the match, Muguruza was nonetheless pushed hard by Mertens, who fought back to beat Jessica Pegula in the quarter-finals after facing three match points.

She led by a set and 5-3 but Mertens continued to come up clutch at key points until Muguruza at last completed the job with a smash in the tie-break.

"You have to be all the time concentrated, otherwise she will come back," she said. "I didn't lose the focus even though I couldn't close it [at first] – I was just looking forward to the next opportunity.

"I didn't think I played bad on the match points. They were just tough points that didn't come to my side. She was very good in defence and on those points, I felt she brought her magic. But I was like, 'Okay, I'm playing well, sooner or later I will convert the match point'. I didn't lose the concentration or get too irritated."

Muguruza will face Barbora Krejcikova in the final, the Czech defeating Jil Teichmann 7-5 6-2.

Krejcikova saved 10 of 11 break points as she reached just the second Tour final of her singles career and has yet to drop a set at this tournament.

The world number 63 is the lowest-ranked singles finalist in history in Dubai, with that previous record held by Virginie Razzano, who was ranked 58 in the world when she lost to Venus Williams in 2009.

Elise Mertens came from behind to clinch a semi-final spot at the Dubai Tennis Championships but Coco Gauff bowed out on Thursday.

Mertens said she "just didn't want to let go" after coming back from the brink to end Jessica Pegula's fine run with a 5-7 7-5 6-0 victory.

The Belgian looked to be heading out when she faced a 5-2 deficit in the second set, yet saved three match points to force a decider.

"I kept on fighting and that was the spirit today," said world number 18 Mertens.

Former world number one Muguruza is Mertens' semi-final opponent, the Spaniard having come from a set down to beat third seed Aryna Sabalenka 3-6 6-3 6-2.

Muguruza lost out to Petra Kvitova in the final of the Qatar Open last week, but looks on top form as she closes in on another championship match.

Sabalenka fell foul of Muguruza in Doha, and the Belarusian was unable to gain revenge as the ninth seed earned a 16th win of the season.

There was to be no place in the last four for 16-year-old Gauff, who came up short against world number 54 Jil Teichmann.

Gauff, who defeated Teichmann twice in Australia in February, was broken to go 5-3 down in the first set and could not respond.

A second break in Teichmann's favour put Gauff on the back foot in the second, and the Swiss then saved three break points to nose into a 3-1 lead.

The contest was settled on Gauff's serve – Teichmann taking the match at the second time of asking to tee up a last-four clash with Barbora Krejcikova, who beat Anastasia Potapova 6-0 6-2 in a little over an hour.

Krejcikova was beaten in the doubles final last year, and has claimed her place in the singles semi-finals of a WTA 1000 event for the first time.

Garbine Muguruza made light work of Iga Swiatek to book her place in the quarter-finals of the Dubai Tennis Championships.

The in-form Spaniard required just one hour and nine minutes to win 6-0 6-4 against the number eight seed and reach the final eight for the fourth time in seven appearances at the tournament.

Reigning French Open champion Swiatek came into the contest on a six-match winning streak but her resistance seemed to falter after she dropped serve in the opening game and then failed to capitalise on two break points in the second.

Muguruza, whose 2021 record now stands at 15 wins and four defeats, was comparatively ruthless against an opponent who landed with just 38 per cent of her first serves.

The former world number one and double grand-slam champion let a 3-1 lead slip in the second set before resuming control through her punishing forehand, getting the job done on the first match point with an ace.

She will be back into action on Thursday against Aryna Sabalenka. The Belarusian, who beat Anett Kontaveit 6-3 6-2, lost in three sets to Muguruza at the Qatar Open last week.

"Back-to-back matches is good," said Muguruza. "That means I'm playing the top players, that means I'm getting into the deep rounds. I'm looking forward for another battle."

Coco Gauff reached the last eight of a WTA 1000 event for the first time after a straight-sets win over qualifier Tereza Martincova.

The American, who turns 17 on the day of the final, won 6-4 6-2 to set up a showdown with Jil Teichmann, a 6-3 6-3 winner over Ons Jabeur.

Second seed Karolina Pliskova was a surprise casualty, losing in less than an hour to Jessica Pegula. The world number 36, who also beat Pliskova in Qatar, will face Elise Mertens after she beat Caroline Garcia 6-4 6-2.

The last remaining former champion in the draw, Belinda Bencic, suffered disappointment on her 24th birthday as she lost 6-1 2-6 7-5 to wildcard Anastasia Potapova. She will take on Barbora Krejcikova, who eliminated Svetlana Kuznetsova.

World number 10 Petra Kvitova says Doha feels like home after taking out her second Qatar Open title in her third final in four years over Garbine Muguruza in Saturday's final.

Kvitova needed little over an hour to get past 16th-ranked Muguruza 6-2 6-1, securing her 28th victory on the WTA Tour and first since winning in Stuttgart in 2019.

The Czech was the Qatar Open runner-up last year to Aryna Sabalenka and champion over Muguruza in 2018, while she did not compete in 2019.

"It's been a great run in Doha," Kvitova said on court post-match.

"It's been a great whole week. I just feel like home a little bit. I love the court, I love everything and the people are really friendly as well."

Two-time Wimbledon champion Kvitova hit 11 winners and was dominant on her serve throughout.

After a strong opening set, Kvitova was broken by Muguruza early in the second but the Czech hit back by winning the next six games to secure the win, extending her head-to-head record over the Spaniard to 5-1.

Muguruza said: "Today I think Petra played very well from the baseline, and it was hard to try to make her move, or try to do much… It really wasn't my day."

Petra Kvitova ended the run of qualifier Jessica Pegula to set up a 2018 final rematch against Garbine Muguruza at the Qatar Open. 

Kvitova saw off Pegula in straight sets, triumphing 6-4 6-4, meaning she will be involved in the final of the tournament for a third time in four years. 

Having twice let slip breaks in the opener, the 2020 runner up edged ahead again at 5-4 before serving out for a 1-0 lead. 

Pegula appeared set to draw level when she raced 3-0 ahead in the next, only to be pegged back by Kvitova, who hit 26 winners and the same number of unforced errors. Victory was eventually sealed after one hour and 18 minutes on court. 

The two-time Wimbledon champion secured the trophy in Doha three years ago by beating Muguruza, who did not even have to hit a ball to progress on Friday after opponent Victoria Azarenka withdrew from their semi-final due to a back injury. 

That title showdown in 2018 went the distance, Kvitova rallying after losing the opening set to eventually prevail. 

"I think it's going to be a tough match," Muguruza said, according to the WTA Tour's official website.  

"We played here in another final three years ago, so just looking forward to playing that match and hopefully getting the trophy." 

The Spaniard has been in impressive form this week, ending Aryna Sabalenka's hopes of defending her crown in the last 16 before thrashing Maria Sakkari in a lopsided quarter-final.

Meanwhile, in Friday's action at the Lyon Open, second seed Fiona Ferro rallied from a set down to beat fellow Frenchwoman Clara Burel and reach the semi-finals. 

Ferro's 2-6 6-1 6-3 triumph means she is certain to break into the top 40 in the world for the first time in her career.  

The only other seed left in the draw is Paula Badosa, the Spaniard knocking out Kristina Mladenovic. Her reward is a last-four clash with qualifier Clara Tauson, conqueror of Camila Giorgi in straight sets. 

Garbine Muguruza made clear she is "fighting for trophies" on the WTA Tour after knocking out defending champion Aryna Sabalenka at the Qatar Open. 

Muguruza prevailed in a high-quality contest that required a third set to decide the outcome, the world number 16 and two-time grand slam champion eventually triumphing 6-2 6-7 (7-5) 6-3 after two hours, 18 minutes on court. 

Sabalenka had won their only previous meeting but the third seed saw her hopes of retaining the trophy dashed, not helped by only managing to convert four of the 13 break-point opportunities she created in the match. 

Muguruza – who matched 41 winners with the same number of unforced errors – finished in fine style, claiming the final four games in a row to set up a meeting with Maria Sakkari, who defeated Madison Keys in straight sets. 

"I'm very motivated to play top players," Muguruza said in her post-match press conference, according to the WTA Tour's website. "Like everybody, I worked hard. I'm fighting for trophies, to play well in big tournaments, in good tournaments. 

"Today I was facing a top player, and I knew I have to go out there with a big, fighting spirit, and be strong to be able to win against these tough opponents." 

While the 2020 winner is no longer involved, former champions Victoria Azarenka and Petra Kvitova both made it beyond the second round with straight-sets wins in Wednesday's action. 

Azarenka, who claimed the title in 2012 and then returned to successfully retain it a year later, saw off qualifier Laura Siegemund 6-4 6-2. 

Kvitova, meanwhile, eased past Anastasia Pavlyuchenkova. The fourth seed went all the way in 2018 and is now into the last eight this year – a 6-1 6-3 result paving the way for a clash with Anett Kontaveit.

Top seed Elina Svitolina is also through – and will face Azarenka next – after needing little over an hour to defeat Misaki Doi 6-1 6-2.

Karolina Pliskova, the second seed, found life far tougher against Ons Jabeur however, eventually coming out on top 6-4 4-6 7-5 in a thriller.

Meanwhile, at the Lyon Open, second seed Fiona Ferro progressed to the last eight on home soil after opponent Tereza Martincova was forced to retire when 4-1 down in the second set, having already lost the opener too.

Alize Cornet is another French favourite hoping to make home advantage tell in the tournament; the fifth seed rallied from a set down to beat compatriot Clara Burel 1-6 6-1 6-3. 

Victoria Azarenka booked her spot in the second round of the Qatar Open with a 6-2 6-3 win over Svetlana Kuznetsova on Monday. 

It was the first time the pair had faced off since the final of the 2016 Miami Open and Azarenka, who won back-to-back titles in Doha in 2012 and 2013, struck first, eventually claiming the opening set in 44 minutes. 

She needed six match points to see off Kuznetsova in the second set to tee up a last-16 meeting with either Laura Siegemund or Elena Rybakina. 

There was also a win for former world number one Garbine Muguruza, who defeated Veronika Kudermetova 6-2 7-6 (7-4).

"Veronika was a very tough opponent," Muguruza told a media conference. "[I'm] just happy with this win. We played a year ago, and I remember it was a tough match. I'm happy to have closed it in two sets."

Fifth seed Kiki Bertens, meanwhile, was dumped out by a rampant Jelena Ostapenko in straight sets. 

The 2017 French Open champion hit 26 winners on her way to an emphatic 6-0 6-2 win against her Dutch opponent, who was playing her first match in five months following Achilles surgery. 

Anett Kontaveit overcame number seven seed beaten Australian Open finalist Jennifer Brady 6-1 6-2 to set up a second-round clash with Angelique Kerber, who beat Cagla Buyukakcay 6-4 6-2.

In the day's other match, Maria Sakkari beat Mayar Sherif 6-0 6-3. 

Meanwhile, teenage qualifier Clara Tauson shocked number one seed Ekaterina Alexandrova 6-3 6-4 in the first round of the Lyon Open. 

There were also wins for Arantxa Rus, Nina Stojanovic, Timea Babos, Greet Minnen and Fiona Ferro in France. 

Simona Halep set up a quarter-final duel with Serena Williams after showing admirable character to battle back from a set down to beat Iga Swiatek 3-6 6-1 6-4 and seal her 100th grand slam match win.

Halep and Swiatek put on a thrilling show in the night session on Sunday, as the Romanian two-time grand slam champion demonstrated her fighting spirit to come from a set down and reach the last eight.

Swiatek took charge in the first set after saving the first two break points of the contest, eventually putting herself in a commanding position as she won the 10 of the final 11 points of the set, but Halep remained focused as her 19-year-old opponent began to wobble in the second.

Halep then snuffed out any threat of a turnaround by breaking back straight after losing on her own service in the decider and she went on to set up a meeting with Williams, who had overpowered Aryna Sabalenka earlier in the day.

Naomi Osaka also advanced, though she was by no means comfortable, while Hsieh Su-wei beat Marketa Vondrousova in straight sets.

HALEP'S REVENGE

Halep's clash with Swiatek was their first since the French Open last October, when Swiatek ran out a 6-1 6-2 winner and went on to claim her maiden major title.

Revenge was on the cards at Melbourne Park and Halep got the job done impressively, showing her mettle to return from a set down.

"Well, I thought before the match that I have to be a little bit more aggressive than Paris. In Paris I have been very far back, and my ball didn't go through the court," the second seed said. "So, I thought that it's a better chance to go and hit.

"The pressure came from the way I played the last match against her. I just expected a better game from myself, which I did, and I'm really happy about that."

Halep accepts facing Williams will be an entirely different challenge, but she remains confident despite lauding the American a "legend" in her on-court interview.

"Of course it's different, she's the only one with 23 grand slams, so you cannot compare Serena with all of us, because we do not have so many grand slams," Halep added.

"But when I step on the court, it's just another opponent, and always I'm focused on myself more than I focus on who I play. We played so many times. I know what to expect. I will just try to do my game, and I will be confident."

WILLIAMS ON COURSE

All eyes are on Williams yet again, as she hopes to equal Margaret Court's record of 24 grand slam titles – and on the evidence of her latest win, she will take some stopping as she won 6-4 2-6 6-4.

Williams revealed she had to cope with a little off-court stress this week with her clothing line, and Sabalenka certainly kept the pressure up as the 22-year-old took the second set.

But Williams responded well to the seventh seed, who became the first player to take a set off the former world number one. Williams said she remained confident despite that setback.

"Like I said on the court, I just felt like even games that I lost, I was so close to winning. Not all games, but probably most of those games," she said. "I just needed to play better on the big points.  I knew that I could. I still hadn't reached my peak. I was like, 'Okay, Serena, you got this, just keep going.'"

OSAKA RELEASES HER ANGER

Osaka was in a real spot of bother against Garbine Muguruza, but saved two match points.

The 2019 champion Osaka steadied herself and felt more composed after a brief show of frustration, as she struck the ground with her racquet.

Ultimately, she emerged a 4-6 6-4 7-5 victor, and Osaka felt letting frustration get the better of her for a moment helped her cause.

"On the first match point, I was just thinking that I didn't hit a decent serve that entire game, so I should really focus on my serve," he said. "I feel like my serve stats were pretty good that set, so I was just telling myself to do better.

"Then on the second point, when the rally started, I just told myself not to push [the ball] but also don't do something crazy and make a really bad unforced error. I felt the entire match I was overthinking. There was a moment when I got angry and hit my racquet on the ground. I feel like I released a lot of the thoughts that I had. It just made me go more into instinct-based tennis."

She will face Hsieh next, the world number 71 having beaten Vondrousova – ranked 51 places higher – 6-4 6-2.

Former Australian Open champion Naomi Osaka saved a pair of match points as she emerged from the jaws of defeat to sensationally prevail against Garbine Muguruza en route to the quarter-finals.

Osaka moved through to the last eight in Melbourne for the second time in three years after the Japanese star and former world number one rallied past two-time grand slam champion Muguruza 4-6 6-4 7-5 on Sunday.

Muguruza – last year's runner-up at Melbourne Park – led 5-3 and was up 40-15 on Osaka's serve in the final set before the latter reeled off four successive games to complete a great escape on Rod Laver Arena.

Winner of the Australian Open in 2019, third seed Osaka had been down 6-4 2-0 earlier in the match when she mounted an improbable fightback against the Spanish star.

It was a milestone moment for Osaka as the three-time major champion celebrated her 50th grand slam victory and extended her winning streak to 18 matches, dating back to February last year after the coronavirus pandemic halted the WTA Tour season in 2020.

Osaka, who hit 40 winners and 11 aces against Muguruza, has gone on to win the title each time after advancing past the last 16 of a slam – US Open in 2018 and 2020 and 2019 Australian Open.

Next up for Osaka is Taiwanese veteran Hsieh Su-wei for a spot in the semi-finals.

Naomi Osaka and Garbine Muguruza set up a blockbuster clash at the Australian Open, while Aryna Sabalenka cannot wait to face Serena Williams.

As Williams was tested before winning through, Osaka and Muguruza raced through their third-round outings in Melbourne on Friday.

Osaka and Muguruza dropped just seven games between them to set up what will be their first meeting, which will take place without fans in attendance as Victoria prepares to move into a five-day lockdown beginning on Saturday due to coronavirus concerns.

Sabalenka also progressed and will next face Williams, while Simona Halep cruised through.

OSAKA, MUGURUZA STORM THROUGH

Osaka, the three-time grand slam champion, brushed past fellow seed Ons Jabeur 6-3 6-2 in the third round.

The Japanese star, winner of the Australian Open in 2019, is looking forward to facing fellow major champion Muguruza.

"I've practised with her once, but it was on grass, and I was younger. It was maybe like a couple years ago," Osaka said.

"But I just remember being really impressed by her, and for me, I've watched her win Wimbledon and win the French Open when I was younger, and I've always wanted to have the chance to play her. So for me, this is really exciting."

A finalist at the Yarra Valley Classic last week, Muguruza's strong start to the Australian Open continued with a 6-1 6-1 thrashing of Zarina Diyas.

"I don't think we've played each other before. Just looking forward for a fourth round, a good fourth round, playing the top players," Muguruza – who has lost just 10 games in the first three rounds – said ahead of facing Osaka. "I feel like that's always the right way, you know, a good sign. Just expecting a good match."

JOB DONE FOR SERENA

Williams' bid for a record-equalling 24th grand slam singles title remains on track after overcoming Russian teenager Anastasia Potapova 7-6 (7-5) 6-2.

In her 101st Australian Open match, Williams secured her 90th career victory in Melbourne. The 39-year-old also improved her overall slam record to 360-51 – Martina Navratilova (306-49) is the only other player to pass 300 wins in the Open Era.

Next up for Williams is Sabalenka, who was too good for Ann Li, winning 6-3 6-1 to reach a major fourth round for just the second time in her career and first in Melbourne.

The Belarusian seventh seed is not daunted by the task facing her when she meets the American for the first time.

"I want to get this thrill. Can I say thrill? I said it right. So it's going to be a thrill. But, yeah. I'm going to do everything I can," Sabalenka said.

HALEP THROUGH AS SEEDS CRUISE

Halep reached the fourth round in Melbourne for the sixth time with a convincing 6-1 6-3 win over Russian 32nd seed Veronika Kudermetova.

Awaiting the two-time major winner in the fourth round is Iga Swiatek after the Polish 15th seed got past Fiona Ferro 6-4 6-3.

Swiatek thrashed Halep 6-1 6-2 on her way to the French Open title last year.

Marketa Vondrousova, the 2019 French Open runner-up, reached the fourth round of the Australian Open for the first time after beating Sorana Cirstea 6-2 6-4.

Up next for the Czech 19th seed is Hsieh Su-wei, who battled past Sara Errani 6-4 2-6 7-5 after two hours and 44 minutes.

Errani had won her previous three meetings with Hsieh in straight sets, including winning a set 6-0 - known as a 'bagel' in tennis parlance - in each of those victories.

It meant Hsieh, 35, had a simple plan against the Italian.

"I don't remember when I lose to someone but someone reminded me I eat the bagel every time so I said, 'Okay, I will try to not take any bagel today'," she said.