Simona Halep has withdrawn from the Miami Open due to a shoulder injury.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

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.

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.

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.

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.

Daria Kasatkina claimed the fourth title of her career after Margarita Gasparyan retired in the second set of the St Petersburg Ladies Trophy final with a back injury.

Kasatkina, who becomes the first player to win two WTA tournaments in 2021 having claimed the Phillip Island Trophy last month, was leading 6-3 2-1 when Gasparyan pulled out.

Gasparyan initially took a medical timeout after losing her first two service games of the match to trail 4-1 before eventually retiring after dropping her serve early in the second set.

Kasatkina's triumph meant she became the first player to win both WTA 500 events on Russian soil, previously claiming the 2018 Moscow title at this level.

The former top-10 player has endured a dip in recent seasons but will be back in the top 50 on Monday, while wildcard Gasparyan's maiden WTA 500 final means she returns to the top 100.

Kasatkina dropped the opening set in her quarter-final and semi-final matches but then swept through the next two sets emphatically on each occasion.

"I'm proud of how I was able to manage the pressure," Kasatkina said, quoted on the WTA website. "I felt differently during this tournament and I'm really proud of that."

Leylah Fernandez and Viktorija Golubic will go head-to-head in the Monterrey Open after progressing on Saturday.

Canadian teenager Fernandez reached her second career WTA Tour singles final thanks to a 7-5 7-5 win over seventh seed Sara Sorribes Tormo.

The 18-year-old Fernandez – whose first final came via last year's Mexican Open in Acapulco, where she lost – converted six of nine break points and hit 35 winners.

Standing in Fernandez's way is Switzerland player Golubic.

Golubic upstaged eighth seed Ann Li 6-2 6-4 to become the first qualifier to advance to the Monterrey Open final in the tournament's history.

The 28-year-old Golubic also reached the Lyon Open final two weeks ago – beaten by Clara Tauson.

Daria Kasatkina and Margarita Gasparyan fended off two of the great stalwarts of Russian tennis to set up a final showdown at the St Petersburg Ladies Trophy.

Kasatkina recovered from a slow start to overcome fourth seed and two-time grand slam winner Svetlana Kuznetsova, after Gasparyan saw off former Wimbledon and US Open runner-up Vera Zvonareva.

Zvonareva, 36, and Gasparyan, whose promising career has been disrupted by injury, were both allocated wildcard entries to the tournament and seized advantage to reach the last four.

Gasparyan, a 26-year-old whose single-handed backhand is an unusual sight in modern tennis, came through the clash with Zvonareva a 6-3 7-6 (11-9) winner to reach her first final at WTA 500 level.

The world number 126 will tackle former top-10 star Kasatkina for the title, after the 23-year-old Barcelona resident scored a remarkable 1-6 6-0 6-2 win over Kuznetsova in the second semi-final.

It was a flat Kasatkina who surrendered the opening set, but she then dashed off eight games in a row, levelling the match and surging to a 2-0 lead in the decider, knocking the stuffing out of 35-year-old Kuznetsova's challenge.

Kasatkina, a 23-year-old with more variety than most, had also dropped the first set 6-1 in her quarter-final win over second seed Veronika Kudermetova on Friday before finding her best game.

She said on Amazon Prime: "Well, why not, if losing the first set will guarantee me victory, why not?"

Kasatkina, the eighth seed this week, won the Phillip Island Trophy in Melbourne last month so is chasing a second WTA title of the year.

She is relishing the clash with Gasparyan, saying: "It's cool to have players of different styles. Tomorrow's a final so you've just got to go out there and try to show your best tennis."

An all-Russian final was already guaranteed, given the host country locked down all four semi-final places, and it will be the 30th such WTA title match.

Eighth seed Ann Li toppled the top remaining seed Zheng Saisai in the quarter-finals of the Monterrey Open on Friday, throwing the field wide open.

Li triumphed 7-5 6-1 over third seed Zheng, who held the highest rank of all remaining players after Sloane Stephens and Nadia Podoroska's first-round exits.

World number 52 Zheng struggled to win on her first serve, with Li converted five of seven break points.

American Li, who is ranked 72nd in the world, will next face Swiss qualifier Viktorija Golubic, who beat Russia's Anna Kalinskaya 6-2 6-4.

On the other side of the draw, Canadian Leylah Fernandez defeated Slovakia's Viktoria Kuzmova 7-5 6-3 and will face seventh seed Sara Sorribes Tormo in the other semi-final.

Sorribes Tormo, who is now the highest ranked remaining player, defeated Anna Karolina Schmiedlova 6-3 7-5.

Daria Kasatkina and wildcard Margarita Gasparyan sank the top two seeds at the St Petersburg Ladies Trophy, where the semi-finals will be all-Russian showdowns.

Ekaterina Alexandrova, the number one seed, fell 6-2 7-5 to Gasparyan, before former top-10 star Kasatkina continued her recent revival by landing a 1-6 6-1 6-2 victory against Veronika Kudermetova.

Friday marked the first time at a WTA tournament that as many as seven of the final eight players have been Russian, and the day's opening clash produced a significant upset.

It was a valid reminder of what might have been for world number 126 Gasparyan, who like Alexandrova is 26 years old but has struggled massively with injuries over the years.

Gasparyan was particularly helped by her superior form on first serve in the opening set, putting 72.7 per cent in court to 44 per cent by her opponent and winning 75 per cent of points when landing that delivery.

A topsy-turvy second set saw a total of seven breaks between the two players, but Gasparyan's 4-3 advantage in that respect helped her clinch a first WTA 500 semi-final appearance.

Up next for her is 36-year-old Vera Zvonareva, the former world number two who beat Anastasia Gasanova 6-3 6-1, saving six of seven break points en route to victory.

Romania's Jaqueline Cristian was the final non-Russian player left in the draw and she certainly tested Svetlana Kuznetsova, but ultimately the 35-year-old fourth seed prevailed 6-7 (5-7) 6-3 6-3.

Next for former US Open and French Open winner Kuznetsova will be Kasatkina, who rounded off the day by shaking off a slow start to look highly impressive against second seed Kudermetova.

The 23-year-old Kasatkina has endured a couple of lean years since entering the top 10 in October 2018 but landed a title last month at the Phillip Island Trophy.

Asked about how she came back from being trounced in the opening set by Kudermetova, Kasatkina said on Amazon Prime: "I think it's just women's tennis and this is what tennis is all about.

"It took me some time to get into this match but at the end I won it."

As for how Saturday's clash with Kuznetsova might play out, Kasatkina said: "We trained many times together but never played in an official match so it's hard to say."

Third seed Zheng Saisai comfortably accounted for countrywoman Zhu Lin to reach the quarter-finals of the Monterrey Open on Thursday.

Zheng, who is ranked 27th in the world, triumphed 6-1 6-2 in a dominant display where she was seldom challenged.

In the last eight, Zheng will face eighth seed Ann Li, who overcame Slovenian Tamara Zidansek 6-4 6-3 at the WTA International tournament.

Zheng is the highest remaining seed left standing in the draw after the first-round exits of top seed Sloane Stephens and Nadia Podoroska.

Russian qualifier Anna Kalinskaya continued her good run with a 6-4 6-3 victory over Nina Stojanovic and she will next face Viktorija Golubic in the quarters – the latter topped Lauren Davis 6-3 6-1.

A record seven Russians will contest the quarter-finals of the St Petersburg Ladies Trophy after victories for seeds Veronika Kudermetova and Daria Kasatkina on Thursday.

Number two seed Kudermetova edged past Kamilla Rakhimova 7-5 3-6 7-6 (7-5), while eighth seed Kasatkina also needed three sets to see off Aliaksandra Sasnovich 5-7 6-3 7-6 (7-2). 

Wildcard Margarita Gasparyan held off Katerina Siniakova 6-4 6-4 and qualifier Anastasia Gasanova shocked fifth seed Anastasia Pavlyuchenkova 1-6 7-6 (10-8) 7-6 (7-4). 

They joined fellow Russians Vera Zvonareva, Ekaterina Alexandrova and Svetlana Kuznetsova in the last eight, with Romanian qualifier Jaqueline Cristian also in the line-up.

The previous highest number of Russians in a WTA quarter-final line-up was six, set at Moscow 2005 when Kuznetsova was joined by Dinara Safina, Elena Dementieva, Maria Sharapova, Anastasia Myskina and Elena Likhovtseva.

The last time a single nation had as many players at this stage of a WTA event was in Oakland in 1993 when the United States produced seven of the eight quarter-finalists.

Canadian teenager Leylah Fernandez booked her spot in the Monterrey Open quarter-finals after easing past Kristina Kucova.

Fernandez cruised into the last eight of the WTA International tournament on Wednesday by defeating Slovakia's Kucova 6-1 6-4 in Mexico.

Kucova had eliminated top seed and 2017 US Open champion Sloane Stephens on Tuesday, but she was no match for the 18-year-old Fernandez midweek.

Next up for Fernandez is Viktoria Kuzmova, who beat lucky loser Harriet Dart 6-4 6-3.

Spanish seventh seed Sara Sorribes Tormo did not have to take to the court, benefiting from a walkover after Kaja Juvan withdrew.

Sorribes Tormo will face Anna Karolina Schmiedlova, who outlasted Jasmine Paolini 2-6 6-2 6-2.

Russian duo Svetlana Kuznetsova and Vera Zvonareva recorded contrasting victories on home soil to reach the last eight of the St. Petersburg Ladies Trophy.  

Kuznetsova - who has won both the French and US Open during her distinguished career - needed just over an hour to get past teenage qualifier Wang Xinyu by a 6-1 7-5 scoreline.  

The 35-year-old converted six of the nine break-point opportunities she created, though was made to work for her win in the second set having previously taken nine of the opening 10 games.  

After failing to serve out for the match when 5-3 ahead, the fourth seed eventually prevailed when recording a break of her own with the score at 6-5.  

Zvonareva, meanwhile, was on court for three hours and 10 minutes as she produced an impressive upset, knocking out third seed Fiona Ferro 6-7 (8-6) 7-5 7-6 (7-2).  

"We both were fighting for every point, trying to hang in there. I think I was able to play some good tennis when it mattered, and I'm happy with the win of course,” Zvonareva said after being involved in the longest match in the history of the tournament, per the WTA's website.  

The 36-year-old came out on top in a deciding tie-break having been unable to hold on to an early 2-0 lead in the set.  

Anastasia Gasanova and Katarina Zavatska had set a new record for the longest contest earlier on Wednesday, the former eventually prevailing 6-2 6-7 (8-6), 7-5 after three hours and four minutes in an eventful first-round tie.

Ekaterina Alexandrova is another Russian player to progress to the last eight, seeing off Tereza Martincova in straight sets.

In the final match, Romanian qualifier Jaqueline Cristian surprised Jelena Ostapenko 6-3 7-6 (11-9) to reach her first ever WTA 500 quarter-final, where her opponent will be Kuznetsova.