Daria Kasatkina reached her second semi-final in as many weeks with a straight-sets victory over Garbine Muguruza at the Sydney Tennis Classic on Wednesday.

The world number 26, who was defeated by Amanda Anisimova in the Melbourne Summer Set 2 semi-finals last week, beat second seed Muguruza 6-4 6-4.

Kasatkina held throughout the opening set, landing 67 per cent of her first serves, and saw the job through in the second despite a couple of early breaks for Muguruza.

It is the Russian's first win over a top-five opponent since beating Caroline Wozniacki at the 2018 French Open.

She will now face fifth seed Paula Badosa, who saw off Olympic gold medallist Belinda Bencic 7-6 (8-6) 3-6 6-3 in an entertaining match lasting two hours and 35 minutes.

The other semi-final in Sydney will be contested between Anett Kontaveit and Barbora Krejcikova, who advanced past Ons Jabeur and Caroline Garcia respectively.

Krejcikova proved far too strong for Garcia, prevailing 6-0 6-2 in 70 minutes, while Kontaveit was in action for just 43 minutes before being handed a walkover win in her match.

Jabeur had targeted "payback" against Kontaveit after her quarter-final opponent pipped her to the final WTA Finals spot in November, but injury cost her the chance to do so.

Having lost the first set 6-4, Jabeur – who eliminated Petra Kvitova in the previous round – felt unable to continue due to a lower back injury.

At the Adelaide International 2, three of the five Americans in action made it through to the semi-finals.

Alison Riske's clash with compatriot Madison Brengle ended early due to the latter retiring with the first set level at 3-3. Tamara Zidansek awaits Riske after beating Lauren Davis 7-6 (7-4) 7-6 (9-7).

Coco Gauff and Madison Keys will meet in the other semi-final, meanwhile, following victories over Ana Konjuh and Ludmilla Samsonova in two and three sets respectively.

Kim Clijsters' first appearance at the Indian Wells Open in a decade did not last long, the two-time champion eliminated in the opening round.

Clijsters remains winless since coming out of retirement on the WTA Tour, falling 6-1 2-6 6-2 to Katerina Siniakova on Thursday. 

A four-time grand slam champion, the 38-year-old Clijsters has lost all five of her singles matches since her return last year. 

"I think overall, there's definitely moments where I'm feeling really good out there, and there's moments where I feel too inconsistent," Clijsters – a winner at Indian Wells in 2003 and 2005 – told reporters.

"That's part of this process in general, it's not going to be a smooth ride, and that's what I'm going to try to improve every time I'm out there."

World number 53 Siniakova converted six of nine break points on Clijsters' serve and moved on to face 10th seed Angelique Kerber at the WTA Premier 1000 event.

GOLUBIC HOLDS OFF VONDROUSOVA

The day's only duel between top-50 players saw world number 46 Viktorija Golubic outlast 37th-ranked Marketa Vondrousova 6-1 4-6 6-3. 

Both players struggled with their own service games, combining for three aces and 17 double faults, but it was the Swiss who managed to convert on eight of 14 break-point chances and come out on top. 

It was Golubic's first win against a player in the top 50 since joining those ranks herself in July; she had been 0-3 against them since then. 

GARCIA RALLIES PAST FLIPKENS, RISKE GETS RARE INDIAN WELLS WIN

Caroline Garcia fought back to defeat Kirsten Flipkens 5-7 6-4 6-0 in a match that took two hours, nine minutes to complete, firing seven aces and winning 71.2 per cent of points on her first serve. 

The Frenchwoman, who had been upset by qualifiers at her two previous tournaments in Ostrava and Chicago, meets 15th seed Coco Gauff in the second round. 

Alison Riske celebrated a victory for just the second time in seven trips to Indian Wells, cruising past qualifier Liang En-shuo 6-2 6-2 to set up a second-round matchup against 16th seed and former US Open champion Bianca Andreescu. 

Bianca Andreescu had little trouble in her first outing on clay this season, easing past Andrea Lazaro Garcia at the Internationaux de Strasbourg.

Andreescu had been absent from the WTA Tour since making the final in Miami back in March, when she was forced to retire when a set and 4-0 down against Ashleigh Barty due to an ankle injury.

A positive COVID-19 test result ruled her out of competing in Madrid and also Rome, though the Canadian showed few signs of rust on her return.

The top seed defeated the world number 279 – who was making her main-draw debut after coming through qualifying – in just 61 minutes, a 6-1 6-2 triumph sealed in a hurry thanks to five breaks of serve.

Champion at the 2019 US Open, Andreescu did not play in any grand slam event last year. She has only featured in the main draw at the French Open once before, reaching the second round at Roland Garros two years ago.

"I feel really, really good," the world number seven said after an impressive opening display. "I had really good preparation coming into this tournament, so I'm super happy."

Also in action on Monday, Yulia Putintseva overcame Sweden’s Rebecca Peterson via a tie-break in the deciding set of their see-saw contest.

The fourth seed eventually prevailed 6-4 3-6 7-6 (7-2) after three hours and 20 minutes on court, booking her a spot in the last 16 of the tournament.

Zhang Shuai was successful in her first outing, beating Misaki Doi 7-5 6-4. Barbora Krejcikova was another seed to make it through, having led 6-3 3-0 when opponent Oceane Dodin retired.

Caroline Garcia overcame Zarina Diyas 7-5 6-2, while Maryna Zanevska needed less than an hour to overcome Yuliya Hatouka 6-2 6-1 and set up a clash with Andreescu.

Jil Teichmann was also a winner in straight sets against Anna Blinkova, but Venus Williams' campaign is over early after going out to Sorana Cirstea, who dominated a decider to triumph 6-1 2-6 6-1.

Coco Gauff continued her fine form with a 6-3 6-3 quarter-final triumph over fellow American Amanda Anisimova at the Emilia-Romagna Open.

In a contest between two teenage stars, it was 17-year-old Gauff who sealed her second semi-final spot in as many weeks, having made the last four at the Internazionali d'Italia.

Third seed Gauff will face Katerina Siniakova next, after the Czech followed up her win over Serena Williams with a 7-5 6-1 defeat of Caroline Garcia.

"I was pretty satisfied with the way I played," Gauff said, after fending off Anisimova.

"I do think I could have served a little bit better, but other than that, I was pretty happy with the way I played."

Despite her valid concerns, Gauff won 72 per cent of points after landing her first serve and forced six breaks to win in style, reeling off six games on the trot from 3-0 behind in the second set.

The other semi-final will see second seed Wang Qiang take on Sloane Stephens.

Wang prevailed 7-6 (7-4) 3-6 7-5 against Petra Martic, while Stephens saw off Sara Errani 6-3 6-0.

It was another rain-affected day at the Serbia Open, where Maria Camila Osorio Serrano managed to get past Kamilla Rakhimova 4-6 6-3 6-4.

Anna Kalinskaya and Reka Luca Jani were locked at one set apiece in the only other match to get started before the weather halted play.

Seeds Petra Martic and Coco Gauff were victorious at the Emilia-Romagna Open on Wednesday, but injury cut short Sara Sorribes Tormo's run in the tournament.

Gauff recorded five breaks of serve as she overcame Italian Camila Giorgi in routine fashion, a 6-2 6-3 triumph securing the third seed a place in the quarter-finals.

The American did have a few issues on her own serve, leading to seven double faults, but ended up winning in one hour and 11 minutes.

Martic, the second seed at the event, was made to work in the first set of her match against Ludmilla Samsonova, both players saving a break point on serve as it went the distance.

There was little to split the pair in the tie-breaker too, Martic edging it 7-5 as she capitalised on her first opportunity to take the set.

The second was more straightforward for the Croatian, an early beak of serve putting her in front before she repeated the trick to wrap up victory in the ninth game.

There were wins in straight sets for fellow seeds Caroline Garcia and Wang Qiang too, as they defeated Anna-Lena Friedsam and Martina Di Giuseppe respectively.

For Garcia, the triumph means a first quarter-final appearance in the 2021 season.

Sorribes Tormo was the only seeded player to exit in the day’s action, the Spaniard forced to retire at 2-2 in the deciding set against Sara Errani due to a problem with her left thigh.

"I'm very sorry for Sara. It was a battle, I know every time we play together it is like this. I was mentally ready to fight, to suffer," Errani said in her on-court interview.

Top seed Serena Williams is already out, beaten in straight sets by Katerina Siniakova to deal the 23-time grand slam champion a further blow ahead of this year's French Open.

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.

Madison Keys is intent on giving Maria Sakkari a second-round test after marking her first WTA Tour appearance since September with a clinical win at the Qatar Open.

American world number 19 Keys, who reached the US Open final in 2017, had not played on tour since losing to Zhang Shuai in the first round of the French Open in late September – she was ruled out of the Australian swing of this season after a positive coronavirus test.

But Keys roared back to action with a thumping 6-4 6-1 victory over Belinda Bencic on Tuesday, the Swiss who last week reached the Adelaide International final.

"I'm really happy with how I came out and played today," Keys said. "I'm a little bit surprised with myself but hoping to keep the momentum going."

Sakkari promises to pose a tricky test for Keys, who is unseeded this week, given the Greek player dropped only three games in her opening win over Mayar Sherif and has shown bright early-season form.

World number 23 Elena Rybakina tripped up in the first round after the Moscow-born Kazakh player lost 7-6 (9-7) 7-6 (7-5) to Germany's 56th-ranked Laura Siegemund at the WTA Premier event.

Jessie Pegula, Anastasia Pavlyuchenkova, Ons Jabeur and Misaki Doi also scored straight-sets victories in Doha.

At the Lyon Open, French players Caroline Garcia and Kristina Mladenovic were both pushed to three sets before inking their places in the last 16.

Third seed Garcia edged compatriot Oceane Dodin 6-2 2-6 6-3, while fourth seed Mladenovic scrambled for a 5-7 7-5 6-2 win over Romanian Mihaela Buzarnescu.

Former Wimbledon runner-up Eugenie Bouchard, in on a wildcard, was bounced out 7-6 (9-7) 6-2 by Aliaksandra Sasnovich, the world number 96 from Belarus.

Danielle Rose Collins will face world number one Ash Barty after beating Zheng Saisai at the WTA Adelaide International.

The American wrapped up a 7-6 (7-5) 6-1 victory and will now face top seed Barty, who will still be smarting from her surprise quarter-final exit at the Australian Open.

Barty is the reigning champion in Adelaide and will be seeking to put that loss to Karolina Muchova firmly behind her.

Collins' compatriot Shelby Rogers also prevailed, beating Veronika Kudermetova 6-3 7-6 (7-4) to set up a clash with third seed Johanna Konta.

Anastasija Sevastova overcame Caroline Garcia 6-2 6-4, while eighth seed Wang Qiang was a 6-4 6-3 winner over teenager Olivia Gadecki.