World number one Iga Swiatek maintained her impressive form by seeing off Aryna Sabalenka in straight sets in Sunday's Stuttgart Open final to win a fourth straight WTA title.

Swiatek was made to work hard in Saturday's semi-final against Liudmila Samsonova as she dropped a rare set, but she was back to her imperious best against Sabalenka.

The 20-year-old prevailed 6-2 6-2 in 84 minutes to make it 23 victories in a row – only five other different players have enjoyed longer winning runs since 2000.

With her latest triumph in Germany, Swiatek has now won 30 WTA matches in 2022, compared to 36 in the whole of 2021.

She has won the Qatar Ladies Open, Indian Wells and Miami Open in straight succession, having also reached the semi-finals of the Australian Open in January.

Sabalenka, who eliminated Paula Badosa, Anett Kontaveit and Bianca Andreescu en route to the final, was the latest player to fall short in trying to stop the sublime Swiatek.

After saving a break point in the opening game, Swiatek held serve and broke her opponent in the next game before comfortably seeing out the first set.

The Pole never looked under serious threat in the second set as she took the last four games to down world number four Sabalenka, who lost to Ash Barty in this final last year.

At the Istanbul Cup, meanwhile, Anastasia Potapova beat Veronika Kudermetova 6-3 6-1 to clinch her maiden career title.

Qualifier Potapova recovered from a set down to beat Yulia Putintseva in Saturday's semi-final and was too strong for Kudermetova in what was her third career final.

Kudermetova broke Potapova early on and led 3-1 in the opening set, but the latter soon found her range and took advantage of some sloppy mistakes from her opponent.

After battling to victory in the first set, Potapova looked far more comfortable in the second as she produced a number of impressive shots en route to a breakthrough triumph.

Naomi Osaka produced a spirited performance as she defeated Sloane Stephens in three sets at Indian Wells on her return to the court.

Osaka was in action for the first time since a shock early exit at the Australian Open in January, but she ultimately had too much for Stephens in a 3-6 6-1 6-2 success.

Stephens initially looked the sharper of the two former major champions in the second-round clash, impressively taking a first-set lead, but Osaka found her groove after a slow start to level the contest.

Osaka then had to save three break points at 2-0 down in the decider, and that appeared to inspire another surge as she rattled off six successive games to roar to an emphatic win.

Shelby Rogers got past Nuria Parrizas-Dias in almost three hours, winning 6-1 5-7 7-6 (7-3), and last week's Monterrey Open runner-up Camila Osorio retired down 6-4 5-0 against Aliaksandra Sasnovich.

Yulia Putintseva got past Ashlyn Krueger 6-3 6-2 and Ukraine's Marta Kostyuk won in three hours and nine minutes over Maryna Zanevska 6-7 (5-7) 7-6 (8-6) 7-5.

Last month's Abierto Zapopan runner-up Marie Bouzkova eased past China's Wang Qiang 6-3 7-6 (7-5), while American Amanda Anisimova defeated compatriot Emma Navarro 6-2 6-2.

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.

Danielle Collins eased past Shelby Rogers 6-4 6-3 to book her spot in the second round at the Silicon Valley Classic on Tuesday.

World number 36 Collins proved too strong for American compatriot Rogers, winning in one hour and 25 minutes.

Collins will meet another American in the second round, with Sloane Stephens up next.

Former U.S. Open winner Stephens beat Caty McNally 6-4 6-2 earlier in the day.

Yulia Putintseva, meanwhile, eased her way into the second round with a 7-5 6-3 win over Croatian Donna Vekic.

Putintseva will face Australian Ajla Tomljanovic in the second round after she fought back to overcome Amanda Anisimova 1-6 7-5 7-5.

France's Kristina Mladenovic won 6-4 6-4 over Han Na-Lae, while American Claire Liu won in three sets against Dayana Yastremska.

Mladenovic will face top seed Elise Mertens, while Liu meets second seed Elena Rybakina.

Yulia Putintseva was in devastating form as she crushed Anhelina Kalinina to win the Hungarian Grand Prix in Budapest, her second career singles title.

She needed just 70 minutes to thrash Kalinina 6-4 6-0 and seal a first WTA Tour triumph since 2019 when she was victorious in Nurnberg.

In fact, her semi-final appearance in Budapest was Putintseva's first since that success in Germany, and she rarely looked like passing up the chance for victory against her Ukrainian opponent.

Kalinina was as much her own worst enemy at times, with 34 unforced errors continuously handing the initiative to the ruthless Putintseva, who converted five of eight break points.

Two of those breaks came in the first three games of the match, and although Kalinina hit back initially, she could not sustain that form as Putintseva closed out the set.

The second set was far more one-sided, as Kalinina took just seven points across the six games, which were all won by Putintseva.

The Kazakh now turns her attention towards the Olympics.

In-form second seed Barbora Krejcikova saw off Wang Xinyu in straight sets on Saturday to set up an all-Czech final with Tereza Martincova on home soil at the Prague Open.

French Open champion Krejcikova needed just one hour and nine minutes to overcome Wang 6-1 6-2 and reach her third final in four tournaments.

Krejcikova controlled the match from the off, on her way to a routine win, with the world number 13 having still yet to drop a single set in the Czech capital.

Martincova had earlier been made to work a little harder for her victory over Greet Minnen, but the number eight seed advanced through to Sunday's final with a 6-3 6-4 win.

The 26-year-old let slip a 4-1 lead in the second set as Minnen pulled it back to 4-4, before taking her second match point with a strong forehand.

At the Lausanne Open, a new singles champion on the WTA Tour will be crowned on Sunday when Tamara Zidansek and Clara Burel face off.

Zidansek proved too strong for semi-final debutant Maryna Zanevska, prevailing 7-5 6-3, while Burel needed to dig deep to get the better of fifth seed Caroline Garcia.

Burel, who unlike Zidansek has never previously reached a WTA singles final at all, was a set and a break down to Garcia but recovered to take the match the distance.

The 20-year-old called a medical timeout in the decider, though she managed to put that behind her as she earned three breaks of serve to stun her French compatriot 5-7 6-2 6-2.

Elsewhere on Saturday, home favourite Dalma Galfi's tournament was brought to an end at the semi-final stage of the Hungarian Grand Prix with a 6-2 3-6 6-2 defeat to top seed Yulia Putintseva.

Wildcard entrant Galfi offered little in the first set to suggest she would push Putintseva all the way, but she did exactly that with a couple of breaks of serve in the second set.

However, Putintseva, looking to add to her only previous singles title at the 2019 Nuremberg Cup, stormed into a 5-1 lead in the deciding set and ended Galfi's hopes with her first match point.

The Russian will next take on Anhelina Kalinina, who led 6-7 (7-5) 4-1 against Danielle Collins in the other semi-final when her opponent withdrew injured.

Rebecca Sramkova handed number-one seed Petra Kvitova a shock defeat on home soil at the Prague Open to record her first WTA Tour-level win in a main draw since 2017.

The unseeded Slovakian took the first set 7-6 (7-5) before Kvitova bounced back to take the next 6-3. Sramkova, however, battled through injury to win the final set 6-4 and upset the two-time Wimbledon winner.

Seventh seed Nina Stojanovic avoided an early exit as she recovered from a first-set loss to beat Vitalia Diatchenko 6-7 (5-7) 6-1 6-3, while ninth seed Greet Minnen defeated Italian Giulia Gatto-Monticone 6-0 4-6 6-1.

Unlike Kvitova, the top seed at the Hungarian Grand Prix, Yulia Putintseva, cruised past Ekaterine Gorgodze 6-2 6-4 to record a straight-sets first-round win in Budapest.

But Irina-Camelia Begu, the fourth favourite, was not as fortunate as she failed to secure second-round progression, falling 3-6 4-6 to the unseeded Anna Karolina Schmiedlova.

The Hungarian Grand Prix provided more shocks, with Irina Bara knocking out eighth seed Sara Errani courtesy of a 4-6 7-5 6-2 triumph, while seventh seed Viktoriya Tomova crashed out to Paula Ormaechea in straight sets.

On day one of the Ladies Open Lausanne, favourite and 2021 Roland Garros semi-finalist Tamara Zidansek shook off a first-set loss to dispatch of Marina Melnikova 2-6 6-3 6-2 and book her place in the next round.

Meanwhile, second seed Fiona Ferro was leading her French compatriot Harmony Tan 7-5 2-1 before play was suspended for the day in Switzerland.

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.

World number one Ash Barty has been knocked out of the Charleston Open after a straight-sets loss to unseeded Spaniard Paula Badosa in Friday's quarter-finals.

Badosa won 6-4 6-3 over the favoured Australian in one hour, 16 minutes to book a spot in the last four on the green clay and a meeting with 15th seed Veronika Kudermetova.

Kudermetova beat 2017 US Open winner Sloane Stephens 6-3 6-4 in her first win over a grand slam winner.

Former French Open junior champion Badosa, who beat fifth seed Belinda Bencic in the second round, claimed her second career victory over a top-20 player against Barty.

Barty may have hit 34 to 19 winners but she also made twice as many unforced errors, 24 to 12.

The Spaniard broke Barty's serve five times while she sent down seven aces and saved 12 of 14 break points.

"I was quite nervous today but I think I served very well and I think that was the key for the match," Badosa said in her on-court interview.

"It was a tough match but I was there until the last moment and I managed to win."

World number 71 Badosa becomes the lowest-ranked player to beat Barty since September 2019.

The Australian had won eight matches in a row after last week's triumph at the Miami Open.

Unseeded Montenegrin Danka Kovinic came from a set down to topple 11th seed Yulia Putintseva 6-7 (2-7) 7-5 6-1.

Kovinic, who knocked out Petra Kvitova in the third round, will play 12th seed Ons Jabeur in the semi-finals after she overcame Coco Gauff 6-3 6-3.

Meanwhile, at the Copa Colsanitas in Bogota, fifth Tamara Zidansek beat Italy's Sara Errani 6-3 6-4 to claim a spot in the semi-finals.

Viktoriya Tomova outlasted qualifier Nuria Parrizas-Diaz 5-7 6-2 6-4 in almost two and a half hours, while Harmony Tan and local wildcard Maria Camila Osorio Serrano also won.

Ash Barty may have her focus on winning the Australian Open right now but suggested a career change could be on the cards in the future.  

The world number one made sure she will still be competing during the second week of the tournament in Melbourne by beating Ekaterina Alexandrova in straight sets.  

But, having played international cricket for Australia before switching to tennis, could the multi-talented Barty be considering trying another sport?  

Elsewhere in Saturday's action, Karolina Pliskova lost her cool – and also a couple of rackets – as she slipped to defeat against the impressive Karolina Muchova in an empty Rod Laver Arena, with fans not able to be present due to a five-day lockdown in the state of Victoria.

Elina Svitolina had no such problems in her third-round match, while Elise Mertens was victorious in just over an hour against Belinda Bencic. Jennifer Brady ended Slovenian qualifier Kaja Juvan's run in the first grand slam of the year.

AUSSIE RULES, OK? 

After winning 6-2 6-4 without ever needing to be at her peak, Barty was cheekily asked by former doubles partner Casey Dellacqua – now working in the media – whether she may be set to switch paths again, once her tennis career has come to an end.  

Australian rules football was the answer – but Dellacqua maybe got more than she bargained for from her former playing partner during the on-court interview. 

"I thought it was our deal, we're going to AFLW. It's ABCD [the nickname for the pairing from their doubles career]. We come as a package, and I know we will be going to the [Richmond] Tigers that is for sure," Barty said. "You can't go to Carlton. You have to come to the 'Tiges' with me."

Dellacqua replied: "I need to get out there and start practicing some kicking, but you are good. I would love to do that one day." 

For Barty, though, the next challenge facing her is Shelby Rogers, who knocked out 21st seed Anett Kontaveit during the evening session.  

MAKING A RACKET 

A disgruntled Pliskova was not impressed when punished for smashing up a racket during her match with compatriot Muchova. 

Having received a warning when throwing a racket to the floor during the course of the final game in the opening set, the sixth seed then vented her frustration again on another while in the players' tunnel.  

An official witnessed the incident and reported it to chair umpire Alison Hughes, who punished the Czech with a point penalty before she began serving to open the second set.  

"It's off court, I'm allowed to do what I want," Pliskova insisted when querying the decision to the official. She would go on to hold before recording two successive breaks, yet somehow failed to force a decider.  

Muchova rallied from 5-0 down in sensational fashion, winning seven games on the spin to triumph 7-5 7-5 to make it through to the last 16.

CONTRASTING PROGRESS FOR SEEDS

Svitolina has still yet to drop a set in the tournament after overcoming 26th seed Yulia Putintseva by a 6-4 6-0 scoreline.  

The fifth seed was twice down a break in the first set but, after eventually coming out on top to take a 1-0 lead, breezed through the second in a hurry.  

"She has a very different game style from what I played my last two rounds, so it wasn't easy at the beginning to adjust," Svitolina said. "As soon as I was feeling better, I just stepped my game, and it was quite a comfortable win after." 

Next up will be Jessica Pegula, who is through to the fourth round at a slam for the first time in her career after thrashing Kristina Mladenovic 6-2 6-1.  

There was also success for another American in the main draw, Brady defeating Juvan in straight sets. Her reward is a clash with Donna Vekic, the 28th seed having to save a match point before eventually seeing off Kaia Kanepi 5-7 7-6 (7-2) 6-4 after two hours and 38 minutes on court. 

Elina Svitolina said playing behind closed doors at the Australian Open felt "a bit disturbing" after having fans in attendance earlier in the week.

The Ukrainian fifth seed booked her spot in the fourth round in Melbourne with a 6-4 6-0 victory over Yulia Putintseva on Saturday.

But no fans were in attendance on Margaret Court Arena as Victoria started a five-day lockdown due to coronavirus.

Svitolina, who will face Jessica Pegula in the last 16, said she felt the difference.

"It was very different conditions. I played a night match at 7:00 with a good crowd. Now it was completely different. It was for sure a bit disturbing, I would say, in some ways sad," she told a news conference.

"But it is what it is. I had to accept. I had to have a good mindset, not thinking too much about that. I just tried to focus on my game."

Svitolina reached the fourth round in Melbourne for the third time in four years after mixing 18 winners with 20 unforced errors.

But the 26-year-old said the lack of fans meant the third-round encounter felt like a practice match.

"It feels like that. I actually had few thoughts about it today. It feels like this. I tried to convince myself that it's a grand slam and that we are playing an important match. I have to focus on my match," Svitolina said.

"But for sure there's some thoughts and there is I say some low moments that can sneak into the mind. It's what we have to deal with. I'm trying my best to do it."

Sofia Kenin and Elina Svitolina fought back from the brink of defeat as both reached the Abu Dhabi Women's Tennis Open quarter-finals on Sunday.

Top seed Kenin fended off a match point in the second set before battling to a 3-6 7-6 (7-5) 6-4 victory over Yulia Putintseva at Zayed Sports City International Tennis Centre.

Putintseva was serving for a straight-sets win at 6-5 up in the second, but the tenacious Kenin forced a tie-break and rallied from 3-1 down to take the third-round match the distance.

The Australian Open champion secured three breaks in the decider to reach the last eight, hitting 35 winners to 25 from 13th seed Putintseva to set up a showdown with Maria Sakkari.

Svitolina, the second seed, was also on the verge of crashing out, but she hung in there to pull off a 6-2 6-7 (5-7) 7-6 (10-8) win over Ekaterina Alexandrova.

The world number five was a break down in the final set and saved two match points in a tense tie-break before finally seeing the back of her Russian opponent.

Ninth seed Sakkari beat two-time grand slam champion Garbine Muguruza 7-5 6-4 to give herself the opportunity to get the better of Kenin for the first time in three attempts.

Aryna Sabalenka stretched her impressive winning streak to 12 matches with a 6-2 6-4 success over Ons Jabeur, while Marta Kostyuk, Sara Sorribes Tormo, Elena Rybakina and Veronika Kudermetova also progressed.

Veronika Kudermetova started the new season in style by beating 10th seed Anett Kontaveit in the first round of the Abu Dhabi Women's Tennis Open on Wednesday.

Kudermetova had won her only two previous singles matches against Kontaveit and maintained that perfect record with a 7-5 6-1 victory.

The world number 46 from Russia broke four times to seal her place in the second round, with Kontaveit winning just 48.4 per cent of points on her first serve in a rusty beginning to the 2021 campaign.

Donna Vekic was another seed to fall at the first hurdle as Bernarda Pera consigned the Croatian to a 7-6 (12-10) 2-6 6-4 defeat at Zayed Sports City International Tennis Centre.

Kirsten Flipkens could face top seed Sofia Kenin in the second round after defeating Laura Siegemund 5-7 7-5 6-4.

Ons Jabeur is aiming to break into the top 10 this year and the 15th seed got up and running for the season by seeing off Anastasia Pavlyuchenkova 7-6 (7-3) 6-3.

Daria Kasatkina, Yulia Putintseva and Ajla Tomljanovic were among the other players who advanced to round two.