Stefanos Tsitsipas battled through to the Miami Open round of 16 and he was joined by Andrey Rublev on Monday.

Greek star and second seed Tsitsipas got the better of 2014 US Open runner-up Kei Nishikori in Miami.

Rublev continued his fine 2021 with a straight-sets demolition of Marton Fucsovics at the ATP 1000 tournament.

In-form Aslan Karatsev, however, bowed out following a surprise loss to Sebastian Korda.

TSITSIPAS HALTS NISHIKORI

Despite a mid-match wobble, Tsitsipas overcame Nishikori 6-3 3-6 6-1 to reach the fourth round.

Former world number four Nishikori forced a deciding set but Tsitsipas withstood the Japanese's comeback.

Tsitsipas, who hit 32 winners, will meet Lorenzo Sonego for a place in the quarter-finals after the 24th seed defeated Daniel Elahi Galan 7-6 (8-6) 6-3.

RUBLEV STAYS HOT

Russian fourth seed Rublev made light work of Fucsovics 6-2 6-1 in just 52 minutes.

Rublev leads the ATP Tour with 18 victories this season after eliminating the in-form Hungarian, ahead of top seed Daniil Medvedev (16-2).

The result secured a third win for Rublev over 29th seed Fucsovics this month.

"I was laughing, because of [the] situation and plus Marton also told me, 'I don't want to see you. I don't want to see you'," Rublev said, cracking a laugh. "[It was] just a situation that [was] fun, and I feel sorry."

Awaiting Rublev is 2014 US Open champion and former world number three Marin Cilic, who beat Lorenzo Musetti 6-3 6-4.

KARATSEV CONQUERED

For only the third time this year, Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev tasted defeat following a 6-3 6-0 loss at the hands of Korda.

American sensation Korda became the first player outside the top five to beat Karatsev this year, with the latter's previous two losses coming against world number one Novak Djokovic and world number four Dominic Thiem.

"It is super special [to reach the Round of 16], especially playing a guy who was as hot as he was," said Korda. "I just took the tactics that I used [against him] at Roland Garros and it worked out really well today."

Diego Schwartzman stands in the way of Korda and the quarters after the fifth seed accounted for Adrian Mannarino 6-1 6-4.

Elsewhere, Denis Shapovalov – the sixth seed – was upstaged by Hubert Hurkacz 6-3 7-6 (8-6).

Another Canadian awaits Hurkacz after 12th seed Milos Raonic was a 6-4 7-5 winner against Ugo Humbert.

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.

Stefanos Tsitsipas continued his strong run of form en route to the Miami Open third round, while Aslan Karatsev's maintained his fairytale run in 2021.

Greek star Tsitsipas flexed his muscles in a straight-sets win over Damir Dzumhur on Saturday.

Australian Open semi-finalist and Dubai Tennis Championships winner Karatsev enjoyed a victorious Miami debut.

Andrey Rublev, Diego Schwartzman, Denis Shapovalov, Marin Cilic and Milos Raonic also progressed at the ATP 1000 tournament.

TSITSIPAS STAYS HOT

World number five Tsitsipas eased past Dzumhur 6-1 6-4 in his first appearance since losing in last week's Mexican Open final.

Tsitsipas (15-4) became the third player to reach 15 wins this season, the second seed following in the footsteps of Russian duo Rublev (17-3) and Daniil Medvedev (15-2).

"It was a great match, especially against a guy that I probably don't have a good record playing against in the past," said Tsitsipas. "I started the match very strong, breaking him twice and taking a big lead in the score, and I think the things worked out by themselves after that."

Tsitsipas will face Kei Nishikori after the Japanese outlasted Aljaz Bedene 7-6 (8-6) 5-7 6-4.

NO STOPPING KARATSEV

Karatsev's Miami Open debut ended in a 6-4 6-3 win for the 17th-seeded Russian over Mikhail Kukushkin.

Already in the ATP's top 100 and set to keep climbing, Karatsev broke serve four times en route to the next round, where Sebastian Korda awaits after upstaging 10th seed Fabio Fognini 1-6 6-4 6-2.

"Of course it gives me confidence to win my first title, but you arrive here and it’s a different surface and new tournament," said Karatsev, who ended last season ranked 112th before bursting into the top 30 behind his semi-final run at Melbourne Park. "So you try [to think of it] as a new tournament and new place, but of course it gives me a lot of confidence."

Karatsev owns a 13-2 record this year, with his only two losses coming against world number one Novak Djokovic and US Open champion Dominic Thiem.

RUBLEV ROLLS ON

Fourth seed Rublev has proven to be remarkably consistent, highlighted by his crushing 6-1 6-2 rain-interrupted victory against Tennys Sandgren.

Having equalled his previous best run in Miami, Rublev will play 29th seed Marton Fucsovics who took down Thanasi Kokkinakis 7-6 (7-3) 6-7 (4-7) 6-4.

Rublev has won a Tour-leading 17 matches this year.

Elsewhere, fifth seed Schwartzman was a 6-3 6-3 winner against Yasutaka Uchiyama, Shapovalov – the sixth seed – trumped Ilya Ivashka 6-7 (5-7) 6-4 6-4 in a marathon, 12th seed Raonic accounted for Jordan Thompson 6-2 6-1, former US Open winner Cilic surprised 13th seed Christian Garin 3-6 7-5 7-6 (7-5), while 15th seed Alex de Minaur was eliminated.

World number one Ash Barty moved through to the last 16 of the Miami Open, where Simona Halep's campaign came to a premature end.

Defending champion and top seed Barty was too good for Jelena Ostapenko in Saturday's showdown between the former French Open winners.

Two-time grand slam winner Victoria Azarenka also moved through to the fourth round of the WTA Premier tournament.

Halep, however, succumbed to a shoulder injury in Miami.

CLASH OF PAST AND PRESENT NUMBER ONES

Barty and former world number one Azarenka will go head-to-head for a place in the quarter-finals.

Australian star Barty accounted for Ostapenko 6-3 6-2 as she extended her winning streak at the Miami Open to eight matches.

Barty, who tallied nine winners to 14 unforced errors, rallied from 2-0 down in the second set by reeling off six successive games to advance.

"Today felt like I was a lot sharper and switched on and ready to go from the very first point," Barty said afterwards.

Three-time Miami champion Azarenka trumped Angelique Kerber 7-5 6-2 in the third round.

Azarenka – the 14th seed – fought back from a 4-1 deficit in the opening set to get the better of the three-time major winner.

"She's a very talented player. I always have been a huge fan of her game and the way she plays, the way she handles herself. She has a lot of variety," Azarenka said on facing Barty. "She has pretty much every single shot there is. [It's] going to be a great match."

INJURED HALEP PULLS OUT

Two-time grand slam champion Halep withdrew due to a shoulder injury as Anastasija Sevastova benefited from a walkover.

"I'm very sorry to I have to pull out of the singles and doubles at the Miami Open, but my injury doesn't let me play here as expected," said Halep.

"I'm sad that I can't continue, I wanted to come here to give my best and play many matches but unfortunately I can't. 

"Hopefully next year I will come back healthy and better."

Next up for Sevastova is wildcard Ana Konjuh, who stunned 15th seed and reigning French Open champion Iga Swiatek 6-4 2-6 6-2.

SVITOLINA AND SABALENKA ROLL ON

Ukrainian fifth seed Elina Svitolina booked her spot in the round of 16 after overcoming fellow seed Ekaterina Alexandrova 7-6 (7-1) 6-4.

Two-time Wimbledon winner Petra Kvitova stands in the way of a quarter-final berth – the ninth seed was too good for 17th seed Johanna Konta 6-1 6-2.

Seventh seed Aryna Sabalenka, meanwhile, prevailed 7-6 (7-4) 6-4 against Veronika Kudermetova.

Belinda Bencic – the 11th seed – was sent packing 4-6 6-4 6-4 by Marketa Vondrousova, who will take on Sabalenka.

Simona Halep has withdrawn from the Miami Open due to a shoulder injury.

Halep beat Caroline Garcia in the second round in Florida on Thursday, but an issue with the world number three's right shoulder prevented her from facing Anastasija Sevastova.

The two-time grand slam champion said: "I'm very sorry to I have to pull out of the singles and doubles at the Miami Open, but my injury doesn't let me play here as expected.

"I'm sad that I can't continue, I wanted to come here to give my best and play many matches but unfortunately I can't. 

"Hopefully next year I will come back healthy and better."

Sevastova will face either French Open champion Iga Swiatek or Ana Konjuh in the round of 16.

Third seed Alexander Zverev was sensationally dumped out of the Miami Open second round as Finnish 21-year-old Emil Ruusuvuori claimed his second top 10 win of his career.

Russuvuori bounced back after losing the first set, changing his tactics and overwhelming the German on Friday to set up a third round meeting with Mikael Ymer.

Ninth seed Grigor Dimitrov also bowed out, going down to Briton Cameron Norrie, while eighth seed David Goffin lost to James Duckworth.

World number two and top seed Daniil Medvedev eased past Lu Yen-hsun, while 11th seed Felix Auger-Aliassime, Karen Khachanov and John Isner all progressed.

TURNAROUND STUNS THIRD SEED

Zverev may have won last week's Mexican Open and the opening set 6-1 against Ruusuvuori but the tables turned quickly as the Finn produced one of the best displays of his career to date.

The 83rd ranked Finn moved regularly to the net and was aggressive in his approach, leaving Zverev rattled before winning 1-6 6-3 6-1 in a stunning momentum shift.

"I don't even know myself," Ruusuvuori said in his on-court interview when asked how he turned the match around.

"I wasn't feeling very comfortable in the first set and I was making a lot of unforced errors but slowly in the second I was starting to feel a bit better... Of course, it's one of the biggest wins in my career so it feels good."

He'll next face Ymer who knocked out 27th seed Nikoloz Basilashvili.

NINTH SEED BUNDLED OUT

Former world number three Dimitrov was ousted from the Miami Open on Friday, losing 7-5 7-5 to 56th ranked Norrie.

The Bulgarian took an early break and served for the first set at 5-3 but Norrie showed his mettle to break back twice to take the opener.

Norrie sent down 10 aces and was strong on serve throughout, claiming a significant win for his burgeoning career.

“It’s huge,” Norrie said. “He’s had a good start to the year. It was such a physical match at the start. He came out really fast and he set the tone at the beginning of the match. Massive one for me and I take a lot of confidence from it.”

Norrie's win sets up a third round meeting with American Taylor Fritz who beat Marcos Giron 6-2 6-2.

DANIIL DOMINATES, GOFFIN SHOCK

Australian Open runner-up Medvedev made light work of Lu, winning 6-2 6-2 to book a third round match with Australian 21-year-old Alexei Popyrin.

Medvedev won in less than an hour, hitting 24 winners and nine aces and making few errors in a clinical display.

Canadian 11th seed Aliassime proved too good for Pierre-Hugues Herbert 6-4 6-4, setting up a third round meeting with 18th seed John Isner who got past qualifier Mackenzie McDonald.

Seventh seed Roberto Bautista Agut progressed by virtue of a walkover against Lloyd Harris who had a wrist issue.

Eighth seed Goffin lost to world number 104 Duckworth 6-3 6-1 in a boilover.

Second seed Naomi Osaka picked up where she left off at last month's Australian Open, winning her first match since lifting the title in Melbourne.

Osaka earned her place in the Miami Open third round on Friday with a hard-fought straight-sets victory over Australian Ajla Tomljanovic.

Australian Open runner-up Jennifer Brady was knocked out in the second round by 58th-ranked Sara Sorribes Tormo.

Brady's defeat was the major surprise on Friday, with Sorribes Tormo fighting back from a set down to win.

Top 10 seeds Karolina Pliskova, Bianca Andreescu and Sofia Kenin also progressed, with the latter coming from a set behind to beat Andrea Petkovic.

OSAKA CONTINUES WINNING RUN

Osaka extended her winning streak to 22 matches, although it was not easy against Tomljanovic.

The Japanese got the edge 7-6 (7-3) 6-4, firing down 36 winners, including 13 aces in a match lasting one hour, 38 minutes.

"This is my first match since Australia, so I just really wanted to play well," Osaka said in her on-court post-match interview. "I kind of feel like I'm at home here, because I grew up [near here] for most of my life."

Tomljanovic did not go down without a fight but was let down by 24 unforced errors.

Osaka will next face Serbian qualifier Nina Stojanovic in the third round.

BRADY BEATEN AGAIN

World number 14 Brady succumbed to in-form Monterrey Open semi-finalist Sorribes Tormo 3-6 6-4 6-1.

Brady had a dream run to the final at the Australian Open last month but came back to earth with a thud against the Spaniard, who has won 10 of her past 11 matches.

The match lasted two hours, 22 minutes, with Sorribes Tormo finding the edge in the last as Brady's first-serve percentage dropped to 30.8 per cent.

Brady's defeat comes a few weeks after being humbled by Anett Kontaveit in less than an hour in the Qatar Open first round.

MIXED BAG FOR SEEDS

Tenth seed Kiki Bertens, in her third match back from Achilles surgery, was knocked out by Russian qualifier Ludmilla Samsonova 6-2 6-1 inside an hour.

Fourth seed and last year's Australian Open champion Kenin responded after losing the first set to defeat Andrea Petkovic, winning 6-7 (6-8) 6-1 6-3. The match was Kenin's first since appendix surgery.

Sixth seed Pliskova comfortably got past Zheng Saisai 6-2 6-1 and 2019 US Open champion Andreescu triumphed over Tereza Martincova 7-6 (7-5) 6-2.

Seeds Elena Rybakina, Kontaveit, Maria Sakkari, Ons Jabeur and Amanda Anisimova all won, with 20th seed Petra Martic and Sloane Stephens both knocked out.

Lorenzo Musetti built on his good form with a first-round victory over Michael Mmoh at the Miami Open on Thursday.

Emerging star Musetti defeated American qualifier Mmoh 6-4 6-4 to set up a second-round meeting with 23rd seed Benoit Paire.

Former US Open champion Marin Cilic also progressed in a three-set victory over Federico Coria, while Thanasi Kokkinakis, Sebastian Korda, Tennys Sandgren and Jordan Thompson were other winners.

Former top-five player Kevin Anderson was among those to bow out in the first round of the ATP 1000 event.

STAR ON THE RISE

Italian teenager Musetti continued his rapid rise with a hard-fought victory over Mmoh.

The 19-year-old Musetti reached the semi-finals of last week's Mexican Open, where he beat both Diego Schwartzman and Grigor Dimitrov en route to the semi-finals.

This week, Musetti battled past wildcard Mmoh in one hour, 38 minutes.

"Last week was a fantastic run in Acapulco," Musetti said in his on-court interview. " I played a really good match, it was a tough match.

"I think my lethal weapon is the backhand down the line."

CILIC SLICE OF FORTUNE

Former world number three Cilic secured his place in the second round with a 6-3 2-6 6-4 victory against Federico Coria.

However, Cilic – the 2014 US Open winner – had a huge slice of luck to claim a break back in the first.

The Croatian got lucky down a break at 2-1 but up 30-40 in the first when he mishit his overhead attempt, striking his frame and bobbling over for a drop shot winner to level.

"It was important for me to keep my head down, keep the focus and just try to get the best level I could today," Cilic said.

FOND MEMORIES FOR THANASI

Australian qualifier Kokkinakis' fond memories in Miami returned with a 6-3 6-3 win over Shintaro Mochizuki as he continues his positive return from a shoulder injury.

Kokkinakis beat then-world number one Roger Federer in Miami in 2018.

Korda won his Miami Open debut match, triumphing 6-3 6-0 over Radu Albot to set up a meeting with 10th seed Fabio Fognini.

Jordan Thompson will face Milos Raonic after accounting for Federico Delbonis 7-6 (8-6) 6-4 in two hours, 12 minutes.

Sandgren – a two-time Australian Open quarter-finalist – got past Pedro Martinez 6-4 2-0, with the Spaniard retiring.

Wimbledon and US Open runner-up Anderson was a surprise casualty, going down 7-6 (8-6) 7-5 to lucky loser Damir Dzumhur.

"I know that my game can be much better than what I'm showing right now and my position in the ATP Rankings can be much better," Dzumhur said.

Ash Barty completed a great escape to stay alive at the Miami Open, where Simona Halep also progressed.

Barty faced a match point but the defending champion and world number one dug deep to prevail in three sets against Kristina Kucova on Thursday.

Romanian third seed Halep also needed three sets at the WTA Premier tournament in Miami.

BARTY PRODUCES COMEBACK

In her first match outside of Australia in more than 12 months, Barty survived to top qualifier Kucova in Miami.

Barty trailed 5-2 in the third set, with Kucova earning a match point at 5-3 but the Australian star saved it and won the final five games of the match to secure a spot in the round of 32.

Winner of the 2019 French Open, Barty sent down an equal career-high 15 aces in two-and-a-half hours.

"Today was really hard work, and I enjoyed every single minute of it," Barty said on court post-game. "There’s nothing like coming through a test like that, and now I get another opportunity in a couple days' time to play another tough match and test myself again."

Next up for Barty is 2017 Roland Garros champion Jelena Ostapenko, who outlasted Kirsten Flipkens 6-2 5-7 6-3.

HALEP REACHES MILESTONE

Halep brought up her 400th WTA main-draw triumph with a 3-6 6-4 6-0 victory over France's Caroline Garcia.

After dropping the opening set, Halep won 11 of the final 12 games to move through to the next round.

Halep won in one hour, 48 minutes, drastically improving on her first serve after the opening set while coming to grips with Garcia's kick serve.

"I needed time to get used to it and to get the rhythm," Halep said about Garcia's serve having improved her head-to-head record to 7-1, with Anastasija Sevastova awaiting in the last 32 after eliminating American sensation Coco Gauff.

Halep received attention on her shoulder early in the second. "I struggled with my serve," Halep said. "I struggled with my shoulder a little bit, so the attention was a little bit on the pain. [After that] I started to relax myself."

KERBER'S DOUBLE BAGEL

Three-time grand slam winner Angelique Kerber has been up and down in recently, but she flexed her muscles with a 6-0 6-0 humiliation of Renata Zarazua.

Aryna Sabalenka – the seventh seed – was another one to fend off match points before rallying 0-6 6-3 7-6 (11-9) past Bulgarian qualifier Tsvetana Pironkova in a gutsy.

Last year's French Open champion Iga Swiatek knocked off Barbora Krejcikova 6-4 6-2, while ninth seed and two-time Wimbledon champion Petra Kvitova got past Aliza Cornet 6-0 6-4.

Fifth seed Elina Svitolina survived to beat Shelby Rogers 3-6 7-5 6-3 and two-time major winner Victoria Azarenka benefited from a walkover.

Vasek Pospisil launched a stunning tirade during his three-set defeat to American qualifier Mackenzie McDonald in the first round of the Miami Open on Wednesday.

The Canadian former world number 25 was docked a point for verbal abuse, subsequently conceding the first set, before a meltdown during the change of ends.

Pospisil used a profanity in reference to ATP chairman Andrea Gaudenzi when speaking to chair umpire Arnaud Gabas.

“[Gaudenzi was] screaming at me in a player meeting for trying to unite the players — for an hour and a half," Pospisil said to Gabas. "If you want to default me, I’ll gladly sue this whole organisation.”

He did fight back to win the second set but ultimately lost to McDonald 6-3 4-6 6-3.

Pospisil, who is nowadays ranked 67th, was joined among the first-round exits by last week's Mexican Open semi-finalist Dominik Koepfer, who went down 6-1 6-4 to wildcard Hugo Gaston as he claimed his first career Masters 1000 win.

Sam Querrey, ranked 63rd, also bowed out 6-3 6-4 to Lu Yen-hsun, who will meet world number two Daniil Medvedev in the second round.

YOUNGSTER BEATS VETERAN

Australian youngster Alexei Popyrin secured his maiden win at the Miami Open, knocking out the oldest player in the draw Feliciano Lopez 6-4 7-6 (7-4).

Popyrin, 21, claimed his first ATP Tour title last month in Singapore and backed that up with a strong display against the 39-year-old former top 20 Spaniard.

Recent Open 13 Marseille runner-up Pierre-Hugues Herbert got past Portugal's Pedro Sousa 6-1 6-3, while South Africa's Lloyd Harris defeated Emilio Nava 6-4 7-6 (9-7).

Frances Tiafoe won in the final match of Wednesday, coming from behind to beat Stefano Travaglia 5-7 6-4 6-2.

COMEBACK CAM

Brit Cameron Norrie produced a heroic final-set fightback to claim his spot in the second round, where he will face Grigor Dimitrov.

Norrie trailed 5-1 in the third set against Yoshihito Nishioka, before winning 6-1 3-6 7-5, winning the last six games to clinch victory.

The 56th-ranked Brit sent down eight aces in the victory, although he got the edge on return and converted seven of his 10 break points.

SECOND ROUND

Top seed Medvedev will face Lu on Thursday, while third seed Alexander Zverev will take on Finland's Emil Ruusuvuori.

Norrie will meet Dimitrov, while 11th seed Felix Auger-Aliassime faces Herbert and eighth seed David Goffin will take on James Duckworth.

Harris has a match-up against seventh seed Roberto Bautista Agut.

Sloane Stephens ended her losing run to start the year with a hard-fought three-set win over France's Oceane Dodin in the first round of the Miami Open on Wednesday.

Former US Open champion Stephens, ranked 49th in the world, defeated Dodin 6-7 (6-8) 6-4 6-2.

Stephens progresses to the second round where the top seeds, including top three Ash Barty, Naomi Osaka and Simona Halep, will be introduced and she will face 28th seed Amanda Anisimova.

Danielle Collins, Wang Qiang, Alize Cornet and Caroline Garcia were among the other winners on Wednesday, while Svetlana Kuznetsova bowed out.

SLOANE FIGHTBACK

Stephens had endured a dismal start to 2021, enduring an 0-4 win-loss record to begin the year.

The 28-year-old American was made to do it the hard way against Dodin on Wednesday, dropping the first set in a tie-break.

Stephens improved on her return in the second set, winning 73 per cent of points off Dodin's second serve before running away with the match in the last.

"It's been a rough one for me lately, so I'm really pleased to get through that, fight my way through it and make it happen somehow," Stephens said post-match.

FORMER MAJOR WINNER GONE

Two-time grand slam winner Kuznetsova was the major first-round casualty, going down 2-6 6-2 6-1 to France's Alize Cornet.

Kuznetsova, who is now ranked 35th in the world, bows out with Cornet to face ninth seed Petra Kvitova.

Collins got past France's Kristina Mladenovic 6-3 6-3 with the 40th-ranked American setting up a second-round clash with 32nd seed Veronika Kudermetova.

Wang, ranked 38th in the world, also progressed despite dropping a set in a 6-1 3-6 6-3 win over Spanish qualifier Aliona Bolsova.

SECOND-ROUND MATCH-UPS

The round of 64 will commence on Thursday, with third seed Halep to face Garcia who got past another Romanian, Mihaela Buzarnescu 6-1 6-2.

Top seed Barty will be in action against Slovakia's Kristina Kucova, while fourth seed Sofia Kenin will take on former top-10 player Andrea Petkovic.

Second seed Osaka has an assignment against 77th-ranked Australian Ajla Tomljanovic, while 14th seed Victoria Azarenka is already into the third round with opponent Laura Siegemund withdrawing after her win on Tuesday.

Three-time champion Venus Williams was dumped out of the Miami Open on Monday in straight sets by Kazakhstan's Zarina Diyas. 

Diyas, ranked 89th in the world, had lost her only previous match against seven-time major winner Williams, but saw off the American 6-2 7-6 (12-10).

"I'm very happy with the win, it was very tough," Diyas said after her victory. "Venus, I looked up to her when I was little, she's such a legend. So for me, it's a really special win."

Elsewhere, Shelby Rogers overcame fellow American Madison Brengle 6-3 6-3 to set up a second-round clash with fifth seed Elina Svitolina.

"I'm really happy to get through that one, she's a really tricky player," Rogers said. "It's actually my first win at this site. The last time I was here, I was spectating, as an injured person! So I'm very happy to be here."

There were also wins for Magda Linette, Sorana Cirstea, Barbora Krejcikova and Kaia Kanepi, while Ajla Tomljanovic beat Anastasia Potapova to seal a clash against second seed Naomi Osaka in the next round.

Andy Murray will not feature at the Miami Open after withdrawing from the tournament because of a groin injury.

The former world number one and three-time grand slam champion has featured only twice on the ATP Tour this season, losing in the first round in Montpellier before going one better in Rotterdam, where he was beaten by Andrey Rublev.

He withdrew from this month's Dubai Tennis Championships to be with his wife as she gave birth to their fourth child.

And his return to action has been delayed again, with Murray missing out on a tournament he has won twice.

The 33-year-old beat Novak Djokovic in the 2009 final and defeated David Ferrer to lift the trophy four years later. He lost to Djokovic in the final in 2012 and 2015.

Murray holds a 28-9 record in Miami, where he had been given a wild card. His place in the draw will be filled by a qualifier or a lucky loser.

The Scot has not competed in a Masters 1000 event since 2016, the next event at that level on the calendar is next month's Monte Carlo Masters.

Juan Martin del Potro will undergo knee surgery for the fourth time but retains hope of playing at the Olympic Games in Tokyo.

Del Potro, who was a career-high world number three in August 2018 and still in the top 10 fewer than two years ago, has not appeared on the ATP Tour since withdrawing from the Queen's Club Championships in 2019.

The 2009 US Open champion had his first procedure after falling at the tournament in London and another followed in January 2020.

The third operation came last August as pain persisted, but the issue still has not been eradicated.

However, Del Potro said in an Instagram post on Monday that the death of his father earlier this year had motivated him to continue pursuing a return to the court.

The 32-year-old, who won bronze for Argentina at the 2012 Olympics and silver four years later, will go under the knife again in Chicago on Tuesday.

"We've tried conservative therapy but the pain is still there," he wrote.

"[Doctor Jorge Chahla] knows I want to play tennis again and be able to play the Olympics, so we agreed that surgery should be done as soon as possible.

"Of course, these last few weeks weren't easy for me. Everything's so hard since my father's passing.

"But also, I feel the strength he sends me from above. I had this day in which I woke up and called the doctor. I knew I had to try again.

"I hope I can overcome this painful situation. I won't stop trying. Of course, your messages and best wishes are always welcomed. Thanks for the love."

Canadian teenager Leylah Fernandez celebrated her maiden WTA Tour title after winning the Monterrey Open in straight sets.

Fernandez broke through with a comfortable 6-1 6-4 victory over qualifier Viktorija Golubic on Sunday.

Featuring in her second WTA final after losing last year's Mexican Open in Acapulco, the 18-year-old Fernandez ensured she got her hands on the trophy this time.

Fernandez did not drop a set throughout the WTA International tournament, easing past her Swiss opponent in one-and-a-half hours.