Elena Rybakina and Tamara Zidansek were both surprise second-round losers at The Rosmalen Grass Court Championships as numerous top seeds fell on Thursday.

Third favourite Rybakina struggled to find her rhythm and fell to a 6-2 6-4 loss against world number 42 Shelby Rogers.

The American will face Kirsten Flipkens in the quarter-finals in the Netherlands after she eased past Ann Li in straight sets.

Aryna Sabalenka, the favourite at the tournament, had little difficulty in negotiating past Arianne Hartono 6-2 6-3 and she will meet Alison van Uytvanck in the next round.

The Belgian picked up the scalp of compatriot Elise Mertens, the eighth seed, with a 6-2 6-3 win over the world number 29.

Fourth seed Zidansek was another to fall as she suffered a 6-1 6-1 loss to Catherine McNally, while Veronika Kudermetova profited from Anna Blinkova retiring with the match heading for one set each.

Belinda Bencic, the second favourite, will next challenge Kudermetova after she bucked the trend of the day with a battling 7-6 (7-2) 6-4 win over Anna Kalinskaya.

Seventh seed Ekaterina Alexandrova had no trouble in advancing, meanwhile, as she saw off Anhelina Kalinina 6-4 6-2.

Maria Sakkari found herself 1-0 down against world number 109 Rebecca Marino before rain stopped play at the Nottingham Open, but the top seed responded to claim a 1-6 6-3 6-3 win.

Third seed Camila Giorgi had no such luck against Hannah Dart as she was eliminated 5-7 6-4 7-6 (7-3), while Alison Riske and Ajla Tomljanovic beat Caroline Garcia and Katie Boulter respectively in straight sets.

World number one Iga Swiatek beat Victoria Azarenka 6-4 6-1 to progress to the quarter-finals of the Internazionali d'Italia in Rome on Thursday. 

Swiatek, who became the first female player to win 25 consecutive matches since Serena Williams in 2015, will face Bianca Andreescu in the last eight after she eased past Petra Martic 6-4 6-4.

"I didn't start well, and everybody could see that," Swiatek told reporters. "I'm really happy with the way I reacted and how I improved in the first set.

"Also how different the second set looked to the first one because I could really reset and really change the way I played. That's the most positive thing for me."

There was a shock in the final game of the day, though, as Daria Kasatkina dumped out number two seed Paula Badosa 6-4 6-4. 

Third seed Aryna Sabalenka sealed a third straight win over Jessica Pegula, easing to a 6-1 6-4 victory, while fourth seed Maria Sakkari defeated Coco Gauff 6-4 7-5.

Seventh seed Danielle Collins was knocked out by unseeded compatriot Amanda Anisimova, the 20-year-old cruising past the Australian Open finalist 6-2 6-2.

There were also victories for Jil Teichmann, who overcame Elena Rybakina 6-7 (3-7) 6-3 7-5, and ninth seed Ons Jabeur, who beat Yulia Putintseva 6-3 6-2.

Naomi Osaka joined several other big names in falling to a second-round exit at the Madrid Open, although Emma Raducanu cruised to a routine straight-sets win over Marta Kostyuk.

Four-time grand slam winner Osaka crashed to a resounding 6-3 6-1 loss to Spain's Sara Sorribes Tormo, exiting her first tournament on clay since the 2021 French Open, where she withdrew citing mental health issues.

Osaka, who had posted an underwhelming 20-15 record on the surface prior to this week, looked uncomfortable throughout and appeared to struggle with a leg injury during a disappointing second set display.

The 24-year-old was not the only high profile player to be on the receiving end of a shock during a day of drama in the Spanish capital, as several of the competition's seeds failed to secure places in the last 16.

Another home favourite, Garbine Muguruza, fell to a resounding loss of her own as Anhelina Kalinina raced to a 6-3 6-0 victory over the seventh seed, while sixth seed Danielle Collins was thrashed 6-1 6-1 by Canadian Bianca Andreescu.

Fourth seed Maria Sakkari was the highest-ranked player in action, and although the world number five won the first set of her clash with Daria Kasatkina, the Greek eventually fell to a 3-6 6-3 6-1 loss, while 2021 US Open runner-up Leylah Fernandez went down 6-4 6-4 to Jil Teichmann.

One big name who did make comfortable progress, however, was Fernandez's US Open conqueror Raducanu, who eased to a 6-2 6-1 win over Kostyuk to set up a last-16 encounter with another Ukrainian in Kalinina. 

The 19-year-old, who has been quoted as saying she believes clay could prove to be her best surface in the future, was delighted with her victory and enjoying the tournament after dropping just one game in the second set.

"I'm definitely happy with my performance," Raducanu said on court. "Marta's a great opponent - I knew it was going to be a really tough battle. I went out there trying to be really aggressive and it paid off.

"It's my first clay court season and I'm really enjoying it. Madrid is such a cool city and it's got such a great vibe about it. I definitely want to try and stay here for as long as possible."

Two top-ten talents have booked a date in the Indian Wells Open semi-final after Maria Sakkari and Paula Badosa won their quarter-finals in straight sets. 

First up, world number six Sakkari took on Ukrainian Elena Rybakina, prevailing 7-5 6-4.

Rybakina won the first three games of the match, working her way to an early 4-1 lead, before her Greek opponent rattled off six of the next seven games to claim the first set.

Sakkari again faced adversity early in the second set, coming back from 40-0 down in the second game to hold serve, before breaking the very next game to pinch the match-winning lead.

Petra Kvitova crashed out of the St Petersburg Ladies Trophy, but Jelena Ostapenko is safely through to the quarter-finals.

Two-time grand slam champion Kvitova was comfortably beaten in straight sets by Irina-Camelia Begu, with the Romanian winning 6-4 6-0 in just one hour and nine minutes.

The effectiveness of the first serve was the main difference-maker, with Begu winning 73.1 per cent of her first-serve points, while Kvitova – who has 28 singles titles to her name in contrast to her opponents' four – could only manage 50 per cent.

Begu was set to face the winner of Tereza Martincova's tie with Elena Rybakina, but the latter withdrew because of illness.

Seventh seed Ostapenko made light work of Andrea Petkovic as she beat the German 6-1 6-2 in just 58 minutes, helped largely by winning 85.3 per cent of her first serves, as well as saving all five of the break points she offered up.

Ostapenko has now won two of her four meetings with Petkovic and will next face Aliaksandra Sasnovich, who eased to a 6-2 6-3 victory over Jaqueline Cristian.

Maria Sakkari and Anett Kontaveit were among the big names to cruise through to the quarter-finals of the St Petersburg Ladies Trophy on Wednesday.

Top seed Sakkari faced Ekaterina Alexandrova in the second round and recorded a routine 6-2 6-4 triumph as she looks to bounce back from a fourth-round exit at the Australian Open. 

The Greek will next face a difficult contest with Elise Mertens, who needed three sets to see off the challenge presented by Petra Martic and seal a 6-4 3-6 6-2 success. 

Second seed Kontaveit recorded a 6-4 7-5 victory over Romania's Sorana Cirstea to set up a tantalising meeting with Belinda Bencic after the Swiss downed Kaja Juvan 6-1 7-6 (7-2). 

World number 12 Elena Rybakina, meanwhile, needed less than an hour to record a straight-sets victory over Varvara Gracheva, booking an encounter with Tereza Martincova in the round of 16. 

US Open champion Emma Raducanu suffered the heaviest defeat of her professional career at the hands of Elena Rybakina at the Sydney Tennis Classic.

The ninth seed needed just 55 minutes to storm to a 6-0 6-1 victory to set up a meeting with Caroline Garcia in round two.

This was only Raducanu's eighth appearance in a WTA main draw and the 19-year old had not played since November having contracted COVID-19 and then withdrawn from the Melbourne Summer Set last week.

Rybakina lost only 11 points on serve in the match, sending down four aces. Raducanu, by contrast, struggled badly: the Briton gave up six double faults and won just two points behind her second serve.

"My serve is a weapon, so I'm always working on it and trying to find some variety," said Rybakina. "For sure, it's my game to play aggressive and my serve is helping a lot."

Elsewhere in Sydney, Olympic gold medallist Belinda Bencic beat Beatriz Haddad Maia 6-3 6-2 in her first match of the year and will now face France's Oceane Dodin.

Home favourite Ajla Tomljanovic defeated Anna Karolina Schmiedlova in straight sets, while world number 20 Elise Mertens also progressed.

At the Adelaide International 2, Coco Gauff looked in strong form as she dispatched Katerina Siniakova 6-1 6-2, while fellow seed Tamara Zidansek beat Heather Watson in a three-set battle.

There was a shock for top seed Aryna Sabalenka, though, as she fell 5-7 6-1 7-5 to Sweden's Rebecca Peterson, who celebrated her first win over a top-five player, while American Lauren Davis beat seventh seed Jil Teichmann in three sets.

Ninth seed Sorana Cirstea lost in straight sets to Anhelina Kalinina, but eighth seed Liudmila Samsonova beat Mayar Sherif.

Ash Barty defeated Elena Rybakina in straight sets to claim the Adelaide International title, while Simona Halep clinched silverware in Melbourne.

World number one and heavy favourite Barty prevailed 6-3 6-2 against Rybakina to claim the Adelaide title for a second time in three seasons.

The 25-year-old recovered from 40-15 down in the seventh game and went on to immediately earn the only break of the opening set.

Barty did not look back as she held throughout the second set, meaning she went 35 consecutive games without losing serve to conclude the tournament.

After securing a 14th WTA singles title in a little over an hour, Barty now turns focus to next week's Sydney Tennis Classic ahead of beginning her Australian Open campaign.

"I feel good leading up to an Australian Open like I have every year," Barty, who hit 17 winners to 13 unforced errors, said after seeing off Rybakina. 

"Each and every preparation is unique. We take it for what comes and what it is, move on, try and do the best that we can in every opportunity.

"It has absolutely no effect on the way that I prepare or the way I'm thinking leading forward just because it's a Grand Slam. It doesn't change for us."

Halep, one of Barty's likely rivals for the Australian Open crown, also made a bright start to the year by overcoming Veronika Kudermetova in the Melbourne Summer Set 1 final.

The number two seed, who is aiming to put last year's injury-ravaged and trophyless season behind her, came out on top 6-2 6-3.

She recovered from an early break down in the first set and again in the second to make it 23 career titles, and a first since the 2020 Italian Open.

It could easily have been a different story, however, as Kudermetova had three break points to move 3-0 ahead in the second set, but the Russian could not take full advantage.

Amanda Anisimova defeated Aliaksandra Sasnovich at the Melbourne Summer Set 2 final to claim the first WTA title of the season, and her second overall.

Belarusian qualifier Sasnovich hit back in style to take the second set 6-1 after losing the opener 7-5, but Anisimova recovered from a break down to edge the deciding set 6-4.

In doing so, Anisimova became the first American to win a title on Australian soil since Sofia Kenin's Australian Open triumph in 2020.

Ash Barty moved a step closer to a second Adelaide International title in three seasons as she crushed defending champion Iga Swiatek's hopes in the semi-finals.

Competing as a stepping stone towards her principal goal of challenging for the Australian Open title later in the month, home favourite Barty sped to a 6-2 6-4 win over the 2020 French Open winner.

She served fewer aces than Swiatek – five to the seven fired down by the 20-year-old Pole – but Barty's powerful forehand proved decisive as she made snappy work of ending the contest.

Barty will face Elena Rybakina in Sunday's final, after the Kazakh beat Japan's Misaki Doi 6-4 6-3. Queenslander Barty beat Dayana Yastremska in the 2020 final.

Having won the French Open and Wimbledon already in her career, Barty will be the favourite at the Australian Open, which begins on January 17 in Melbourne.

The world number one, by seeing off ninth-ranked Swiatek, boosted her win-loss record against top-10 WTA rivals to 8-1 since the beginning of last year.

Barty said, quoted on the WTA website: "It is exciting to be able to play well here in Australia. This is where I want to play my best tennis. I want to give myself an opportunity to play for titles in Australia.

"It's something really exciting to start the year off as an Aussie player in front of our home fans."

Reflecting on a positive performance, Barty, who has also reached the doubles final with Storm Sanders, said: "I felt like on Iga's service games I was able to get into most of them, which is important when you're playing someone who can dominate with that first ball and first strike.

"I felt like I was able to build pressure over time, making her play a lot of balls on her service games, not giving her too many cheapies."

Swiatek is entered into next week's Sydney Classic and learned on Saturday that she faces a testing opener there, having been drawn to face Great Britain's US Open champion Emma Raducanu in a standout first-round match.

At the Melbourne Summer Set 2 tournament, Russian third seed Daria Kasatkina suffered a shock 6-2 6-0 semi-final defeat at the hands of American world number 78 Amanda Anisimova.

Anisimova goes on to face fellow unseeded player Aliaksandra Sasnovich for the title, after the Belarusian beat American Ann Li 7-6 (7-4) 2-6 6-3.

Petra Kvitova was on the receiving end of an upset in the first round of the WTA International in Adelaide as she was surprisingly beaten by wildcard Priscilla Hon on Monday.

Two-time Wimbledon champion Kvitova, who ended 2021 among the world's top 20 players for the first time since 2016, lost in three sets to her Australian opponent 6-7 (4-7) 7-5 6-2. The victory was Hon's first ever against a player in the top 40.

Elsewhere, number three seed Maria Sakkari saw off Slovenia's Tamara Zidansek 6-2 0-6 6-4, while number seven seed Elena Rybakina earned a 6-4 1-6 6-1 win over Storm Sanders.

Leylah Fernandez, the 2021 US Open runner-up, also looked comfortable in a straight-sets victory against Ekaterina Alexandrova, easing past the Russian 6-3 6-4. The 19-year-old will face either number five seed Iga Swiatek or Daria Saville in the next round.

Heather Watson is out after a 6-4 7-6 (7-5) loss to home favourite Ajla Tomljanovic, while in the doubles event, Japanese pair and top seeds Ena Shibahara and Shuko Aoyama were beaten 6-4 6-2 by Victoria Azarenka and Paula Badosa, who will play against one another in the singles on Tuesday.

Olympic gold medallist Belinda Bencic eased to a straight-sets win over Sara Sorribes Tormo to maintain her good form and book a place in the Ostrava Open quarter-finals.

Third seed Bencic needed just 88 minutes to see off her 36th-ranked opponent as she made it 15 victories from her past 18 matches.

Czech wildcard Tereza Martincova is also through to the last eight on home soil after battling past French Open finalist Anastasia Pavlyuchenkova 7-6 (7-5) 7-6 (8-6).

Martincova is into her fifth quarter-final of the season and will take on number four seed Maria Sakkari, who saw off Jelena Ostapenko 6-4 6-2 earlier on Thursday.

Also through to round three is Elena Rybakina following a hard-fought 6-3 2-6 6-1 win over qualifier Magda Linette, while Jil Teichmann – who shocked former world number one Angelique Kerber in the previous round – advanced in three sets against Alison Riske.

She will face Petra Kvitova for a place in the semi-finals. 

Top-seeded Elise Mertens rolled into the semi-finals at the Silicon Valley Classic with a 6-3 7-6 (10-8) win over Yulia Putintseva on Friday. 

The Belgian already has collected a pair of grand slam doubles titles this year at the Australian Open and Wimbledon and is seeking her seventh career singles crown. 

She will need to get past fourth seed Daria Kasatkina to have a chance. 

The Russian outlasted Magda Linette 6-4 3-6 6-4 in her quarter-final and is seeking her third title of 2021 after a three-year drought between wins. 

The other semi-final will match seventh seed Danielle Collins against qualifier Ana Konjuh.

Collins pulled out a tight 7-6 (7-5) 7-6 (7-4) upset of second seed Elena Rybakina to reach the semis in San Jose for the second time. 

The American won her eighth consecutive match after taking the title at Palermo two weeks ago. 

She will meet the only unseeded player remaining, Konjuh, who won the final 10 games of the match to close out Zhang Shuai 3-6 6-2 6-0. 

Top-seeded Elise Mertens pulled out a three-set win to reach the quarter-finals at the Silicon Valley Classic as all four matches went the distance on Thursday.

The Belgian, ranked 17th in the world, prevailed 6-2 4-6 6-4 over Kristina Mladenovic of France in two hours and 40 minutes to advance in San Jose.

She moves on to face the eighth seed, Yulia Putintseva, who rallied past Ajla Tomljanovic 3-6 7-5 6-3 as the Australian blew numerous chances to pull ahead by converting only two of 16 break-point opportunities.

In the bottom half of the draw, second seed Elena Rybakina remained on track with a 2-6 6-0 6-2 victory over American Claire Liu in a rematch of a second-round meeting at Wimbledon.

Rybakina next meets seventh seed Danielle Collins, a 3-6 6-4 6-3 winner over US countrywoman Sloane Stephens.

Stephens, the 2017 US Open champion, has slipped to number 67 in the world and was playing in her first tournament since Wimbledon as she prepares for a return to Flushing Meadows.

Camila Giorgi extended her strong run at the Viking International in Eastbourne as she dumped out top seed Aryna Sabalenka on Thursday.

The Italian had already beaten defending champion Karolina Pliskova en route to the last eight and pulled off another upset as she claimed a 7-6 (7-5) 0-6 6-4 win over Sabalenka.

Giorgi's bid for the third WTA Tour title of her career will now continue with a semi-final against Anett Kontaveit on Friday.

The Estonian also needed three sets to book her place, bouncing back from losing the opener to beat Viktorija Golubic 2-6 7-6 (7-2) 7-5.

Daria Kasatkina was unable to build on her win over fourth seed Iga Swiatek in the last round as she missed out on a spot in the semi-finals.

The Russian took the first set against Jelena Ostapenko but failed to build on that success as the Latvian ran out a 1-6 7-5 6-2 winner.

In the final match of the day, Anastasija Sevastova was beaten by Elena Rybakina, who had earned her place in the quarters by beating second seed Elina Svitolina the day before.

World number 61 Sevastova, who eliminated Coco Gauff, won the first set 6-2, but Rybakina fought back to claim the next two 7-6 (9-7) 7-6 (7-5).

Rainy conditions ensured there was no play at this week's other WTA event held in Bad Homburg, Germany, though one player was able to secure passage to the semi-finals.

Sara Sorribes Tormo claimed her place in the next round after Victoria Azarenka, her scheduled opponent, pulled out due to injury.

Second seed Elina Svitolina crashed out of the Viking International in Eastbourne at the last-16 stage on Wednesday with a straight sets defeat to Elena Rybakina.

The world number five lost 6-4 7-6 (7-3) to 21st-ranked Rybakina, whose reward is a meeting with Coco Gauff's conqueror Anastasija Sevastova in the quarter-finals.

Third seed Bianca Andreescu of Canada also lost in straight sets, Anett Kontaveit of Estonia beating her 6-3 6-3.

And it was the same story for fourth seed Iga Swiatek, though she at least took a set as she was beaten by Daria Kasatkina.

It took an impressive rally from Russia's Kasatkina to bounce back from losing the first en route to a 4-6 6-0 6-1 success.

She will now face Jelena Ostapenko, who beat Ons Jabeur 5-7 6-4 6-3.

In fact, top seed Aryna Sabalenka was the only seed to avoid a surprise exit on Wednesday as she cruised through.

The Belarussian, ranked fourth in the world, beat Alison Riske 6-1 6-4 in just over an hour to set up a clash with Camila Giorgi.

Giorgi had earlier followed up a win over defending champion Karolina Pliskova in the last round by beating Shelby Rogers 6-3 4-6 6-2.

There was no such string of shocks at Wednesday's other WTA event, the Bad Homburg Open in Germany, though first and second seeds Petra Kvitova and Victoria Azarenka needed three sets to progress.

Kvitova lost a second-set tie-break as she beat Ann Li 6-2 6-7 (4-7) 6-1 to reach the quarters, while Azarenka defeated Alize Cornet 6-4 3-6 7-6 (9-7).

Angelique Kerber, the fourth seed, progressed more smoothly, earning a comfortable 6-0 6-2 win over Russia's Anna Blinkova.

And Nadia Podoroska saw off the challenge of Patricia Maria Tig, winning 7-6 (7-4) 2-6 6-4.