Coco Gauff won the battle of the American teenagers as she progressed into the San Diego Open second round with a 6-3 6-3 over Robin Montgomery on Wednesday.

The 2022 French Open finalist beat fellow 18-year-old Montgomery in a rain-affected match in one hour and 23 minutes, to clinch a last-16 clash with Bianca Andreescu.

The match marked Gauff's first game on tour since losing to Caroline Garcia in the US Open quarter-finals last month, although she had to endure an overnight rain delay, resuming on Wednesday up 6-3 3-2.

Gauff only needed 20 minutes on Wednesday to close out the victory, finishing the match with 3-0 aces, winning 76 per cent on her first serve and converting four of seven break points.

Croatian qualifier Donna Vekic continued her strong run with a 6-3 6-2 win over 2022 US Open quarter-finalist Karolina Pliskova. Vekic moved into the third round, having beaten Maria Sakkari in the first round too.

Fourth seed Jessica Pegula eased her way into the third round with a 6-3 6-1 victory over wild card Coco Vandeweghe in only 69 minutes. Pegula can secure her first WTA Finals qualification this week.

Danielle Collins was another American victor, triumphing 6-2 6-4 over Italy's Martina Trevisan in one hour and 27 minutes, reaching her third quarter-final of the year.

Iga Swiatek may be the world number one and have had a 37-match winning streak this year but says she is surprised to reach this week's US Open semi-finals.

Swiatek qualified for her third grand slam semi-final for the season with a 6-3 7-6 (7-4) victory over American eighth seed Jessica Pegula in one hour and 53 minutes on Wednesday.

The 2022 French Open champion and 2022 Australian Open semi-finalist became the first women's top seed to reach the last four at Flushing Meadows since Serena Williams in 2016.

The victory comes after Swiatek's 37-match winning streak was ended in the third round at Wimbledon in June by Alize Cornet, winning four out of seven matches at three tournaments following that as the WTA Tour moved to hard courts in the lead-up to the US Open.

Swiatek expressed her surprise at making the last four during her on-court interview after the match and explained that, following early losses in the lead-up tournaments in Cincinnati and Toronto.

"Looking logically at the last tournaments, I just didn't know if this one is going to be possible for me to be consistent and to win so many matches in a row," Swiatek told reporters.

"I feel like I've been playing better and better every week since the start of this swing. So it surprised me because after the losses that I had in Toronto and Cincinnati, I just wasn't expecting to play so well here.

"It gave me actually a lot because I could be kind of an underdog again, not maybe fully, but just not expect from myself that I'm going to win everything right now."

The Pole said her game "clicked" against Pegula, hitting 22 winners compared to the American's 14, winning 43-of-71 points on return.

"I'm pretty proud of it because I feel like I'm playing better and better every match," she said.

"Jessie was a tough opponent today, for sure. Second set was really tight. We both were fighting till the last point. I'm proud of myself that I could be the one to win the last one."

Swiatek will take on Aryna Sabalenka in the semi-finals, while Pegula bows out having reached the quarter-finals at three of the four majors this year.

"I go back and forth, I should be positive," Pegula said. "At the same time I'm like, three quarterfinals. Sorry, but it sucks. It sucks.

"I wish I could have done it here at my home slam, but I guess not. I wish I didn't have to play Iga every quarter-final or Ash Barty, which seem to be the two people that don't really lose that often. So it just sucks.

"I had a great year at the slams. I know there's still some tournaments left. I'm a little deflated right now. I'm not real happy. It just sucks to lose. I just wish it would have been different tonight."

World number one Iga Swiatek has continued her commanding 2022 season with a straight-sets victory over eighth seed Jessica Pegula securing her spot in the US Open semi-finals for the first time.

The Pole, who won this year's French Open and went on a 37-match winning streak until her third-round Wimbledon defeat, triumphed 6-3 7-6 (7-4) in one hour and 53 minutes in a match full of breaks.

Swiatek's victory, her 55th of the season, clinched a semi-final date with sixth seed Aryna Sabalenka, who fell in the last four at last year's US Open.

The 21-year-old became the first women's top seed to reach the US Open semi-finals since Serena Williams in 2016, while she is the only previous grand slam winner remaining in the draw.

In a match that was far from a classic, Swiatek fought back from a break down in the first set to take the advantage, before a second frame that included 10 breaks, with the Pole edging home in a tie-break.

Pegula broke Swiatek in the fifth game to lead 3-2 in the first set but the Pole responded emphatically, going on a sequence where she won 14 of 15 points to secure the set.

Swiatek appeared ready to run away with the match when she immediately broke the American in the first game of the second set but that merely set the tone, with both players struggling to hold on serve.

The world number one served twice for the match but faltered, forcing a tie-break which the Pole won, converting her first match poinit.

Data slam: Breaks galore in tense battle

Holding serve proved challenging in a tense match, with 13 games broken out of the 21 played, including 10 of those coming in the second set. Swiatek had broken serve 57 per cent of her return games during the US Open coming in.

Both players also had more unforced errors than winners, with Swiatek's 21 winners ultimately proving the difference in class. It was Swiatek's eighth win over a top-10 opponent in a row in straight sets.

ACES/DOUBLE FAULTS

Swiatek – 1/3
Pegula – 1/3

WINNERS/UNFORCED ERRORS

Swiatek – 21/32
Pegula – 14/29

BREAK POINTS WON

Swiatek – 7/11
Pegula – 6/10

After defeating Julie Niemeier in a less than inspiring showing, Iga Swiatek feels the race for the US Open title is wide open, and any of the women remaining in the quarter-finals can go all the way

In an uncharacteristic opening set from the world number one, Swiatek had her serve broken in the very first game, and conceded another break to drop the frame 6-2.

She fought back in the second as they traded breaks of serve, with only three successful holds from 10 games as Swiatek took it 6-4, before really finding her groove in the third to run away with a 6-0 finish.

It was her 19th 'bagel' set of the season, with only Serena Williams in 2013 (25) posting more 6-0 sets in a single year since 2000.

When asked about that record, Swiatek said she is aware of it, and that she enjoys Twitter memes referring to "Iga Swiatek's Bakery", although she did not wish to discuss any potential records.

Instead, she discussed the work she has been putting in on the hard courts, having never made the US Open quarter-final before this run.

"For sure, hard court is our goal at the beginning of the season, not the end of the season," she said. "Also we're mainly practicing on hard court pre-season. 

"These are the courts that basically are going to show me where my level of tennis is.

"I played too many matches this year to get, like, huge excitement honestly. But for sure today I'm the most excited because the quarter-final is my best result right now. 

"I'm just happy that I did a better job than last year and I'm going to push forward."

Swiatek was complimentary about her next opponent, Jessica Pegula, admitting "she has a game style that suits these courts", but she pointed out how many emerging players are on the tour at the moment and how it may simply come down to who can handle the big moments.

"I guess it's going to show who's going to cope with being in a new situation better," she said.

"But I think it's just exciting for all of us. It also shows that anything can happen, and anybody can win this tournament."

Simona Halep came from a set behind to defeat seventh seed Jessica Pegula 2-6 6-3 6-4 in the semi-final of the Canadian Open on Saturday, booking her place in the final against Beatriz Haddad Maia.

Romania's Halep, the 15th seed, struggled to return Pegula's serve in the opening set, winning just 32 per cent (nine-of-28) of her return points while compounding her early issues with four double faults.

Whether Pegula began to run out of steam, or Halep figured something out, she had significantly more success against the American's serve the rest of the way, winning 55 per cent (12-of-22) of her return points in the second set, and 57 per cent (20-of-35) in the decider.

Halep has now won 11 of her past 13 matches, and Pegula is her third consecutive win against a top-25 opponent after defeating both world number 21 Jil Teichmann and world number 13 Coco Gauff in straight sets. 

While this will be Halep's 18th career WTA 1000 final, it will be Haddad Maia's first, after she emerged triumphant 6-4 7-6 (9-7) against 14th seed Karolina Pliskova.

She did not have a serving advantage against Pliskova, who won the ace count nine-to-one, but she was gritty, saving four of the six break points she faced, and refused to concede the second set after dropping the first three games.

Haddad Maia – the only Brazilian ranked inside the top-100 – has now beaten five consecutive top-25 opponents on her way to the final, including world number one Iga Swiatek, Olympic gold medalist Belinda Bencic and Canadian hometown hero Leylah Fernandez.

Two-time major winner Simona Halep continues to find form ahead of the upcoming US Open with a 6-4 7-6 (7-2) victory over Coco Gauff clinching her spot in the Canadian Open semi-finals.

Halep defeated 10th seed Gauff, who had beaten Naomi Osaka, Elena Rybakina and Aryna Sabalenka this week, in one hour and 47 minutes.

The Romanian 15th seed was broken five times and sent down eight double faults, but found the edge with speed, finesse and power.

The win means Halep has won the third most matches (36-10) on the WTA Tour this season, behind only top-ranked Iga Swiatek (49) and Wimbledon finalist Ons Jabeir (37).

Halep's improved form comes after she teamed up with Serena Williams' ex-coach Patrick Mouratoglou in April following a difficult 2021 season.

"Before I met him I was super down with my motivation," Halep told reporters. "I couldn't really work, keep working. I was almost done with tennis. He brought this fire back and the motivation. He trusted that I still can play good tennis and he transferred this to me."

The 2018 French Open and 2019 Wimbledon champion added: "Physically I'm good. Mentally I'm good, so I think it's all positive."

Halep, who won the Canadian Open in 2018, has reached the semi-finals for the fifth time in her career where she will take on seventh seed Jessica Pegula.

Pegula got past Yulia Putintseva 6-3 6-3 in one hour and 21 minutes. Qualifying for the last four at the Canadian Open for the second straight year.

Brazilian Beatriz Haddad Maia maintained her Canadian Open run, having ousted Swiatek in the third round and local favourite Leylah Fernandez in the second, with a 2-6 6-3 6-3 victory over Tokyo Olympics gold medalist Belinda Bencic in two hours and 11 minutes.

Haddad Maia became the first Brazilian to reach the semi-finals of a WTA 1000 tournament. She will face Karolina Pliskova in the semi-finals after the Czech 14th seed beat Qinwen Zheng 4-6 6-4 6-4.

Coco Gauff will reach the highest ranking of her career after the 18-year-old defeated world number six Aryna Sabalenka 7-5 4-6 7-6 (7-4) in the third round of the Canadian Open on Thursday.

Gauff, who has never been ranked higher than her current spot of 11th, will overtake Emma Raducanu and likely Daria Kasatkina to move up to ninth when the next rankings are released after prevailing in an exceptionally tight match against her Belarussian opponent. 

Incredibly, both Gauff and Sabalenka won exactly 131 points each, posting identical success rates on service points (77-of-131) and return points (54-of-131).

Gauff will be considered one of the favourites in the tournament after world number one Iga Swiatek was sensationally eliminated by Brazil's Beatriz Haddad Maia. Swiatek was sloppy, committing nine double faults to just one from her opponent.

Two-time grand slam winner Simona Halep defeated rising Swiss talent Jil Teichmann 6-2 7-5, utilising her dominant first serve to get the job done. Halep converted 82 per cent (32-of-39) of her accurate first serves into points, compared to just 59 per cent (29-of-49) for Teichmann.

World number seven Jessica Pegula had to save a match point on her way to a comeback 3-6 6-0 7-5 win against reigning Canadian Open champion Camila Giorgi, booking her quarter-final clash against Yulia Putintseva after the Kazakhstani beat Alison Riske 6-3 7-5.

Third seed Maria Sakkari went down 1-6 7-6 (11-9) 3-6 against 14th seed Karolina Pliskova, and the Czech will take on China's Qinweng Zheng after she eliminated Canada's last remaining contender Bianca Andreescu 7-5 5-7 6-2.

In the final match of the night, Tokyo Olympics gold medalist Belinda Bencic was incredibly impressive against world number eight Garbine Muguruza, prevailing 6-1 6-3.

Second and third seeds Paula Badosa and Ons Jabeur eased into the Silicon Valley Classic quarter-finals on Wednesday, while Simona Halep and Jessica Pegula were bundled out of the Citi Open.

Last month's Wimbledon finalist Jabeur proved too good for American Madison Keys 7-5 6-1, winning in one hour and 22 minutes.

Jabeur, playing for the first time since Wimbledon, converted six of nine break points for the match, dominating the second set where she won 90.9 per cent first serve points.

Second seed Badosa survived a scare to win over qualifier Elizabeth Mandlik 6-2 5-7 7-6 (7-5) in two hours and 31 minutes.

Eighth seed Karolina Pliskova was knocked out by American Amanda Anisimova 3-6 7-5 6-1, while last year's runner-up Daria Kasatkina beat Taylor Townsend 6-4 6-0.

Two-time major winner Halep was forced to retire due to illness and top seed Jessica Pegula was bundled out by Daria Saville at the Citi Open.

In warm conditions, the 30-year-old Romanian battled throughout the match but eventually retired down 7-5 2-0 to Anna Kalinskaya after one hour and six minutes.

Halep had fought back from a 4-0 deficit in the first set to square it up at 5-5, before losing the first set.

However, the former world number one succumbed to illness early in the second set, handing Kalinskaya her passage into the quarter-finals.

On a dramatic day for the Citi Open favourites, world number seven Pegula was eliminated by Saville in straight sets in one hour and 38 minutes, 7-5 6-4.

Pegula was not helped by a first-serve percentage of 44.8 per cent, while she struggled to convert break points, with the Australian saving nine of 10 for the match.

Saville's win means she is 3-3 against top 20 opponents this year, progressing into the last eight where she will face Canadian qualifier Rebecca Marino.

Marino, who beat Venus Williams in her return to singles in the first round on Monday, knocked off Germany's Andrea Petkovic 6-3 3-6 6-1.

Estonian sixth seed Kaia Kanepi progressed into the quarters where she will face Kalinskaya after beating China's Zhu Lin 4-6 6-4 6-4.

Elena Rybakina has been bundled out of the first round of the Silicon Valley Classic by Daria Kasatkina in her first game since her Wimbledon triumph last month.

Rybakina won the first set comfortably before the Russian hit back for a remarkable turnaround win, 1-6 6-2 6-0 in one hour and 40 minutes.

Seventh seed Kasatkina was the runner-up at last year's Silicon Valley Classic and found her groove to break her Rybakina six times in the second and third sets.

Rybakina sent down three of her four aces for the match in the first set, but Kasatkina adjusted to her serve and won 52.1 per cent return points for the match.

Eighth seed Karolina Pliskova fought back from a slow start to get past Katie Boulter 1-6 7-6 (7-5) 6-3, despite 16 double faults.

American Amanda Anisimova overcame compatriot Ashlyn Krueger 6-2 7-6 (7-5). US pair Madison Keys and Taylor Townsend were also winners.

Third seed Simona Halep and top seed Jessica Pegula were both among the winners in the first round at the Citi Open in Washington DC.

Two-time major winner Halep cruised past Spanish qualifier Cristina Bucsa 6-3 7-5 in one hour and 20 minutes.

Halep, playing her first match since her Wimbledon semi-final loss to Rybakina, fired 19 winners but also 33 unforced errors.

Defending champion Pegula made light work of countrywoman Hailey Baptiste 6-2 6-2 in 73 minutes.

Pegula will face unseeded Australian Daria Saville, who won in three sets over Mirjam Bjorklund, while sixth seed Kaia Kanepi will meet China's Zhu Lin after both won on Monday.

Fifth seed Elise Mertens was a first-round casualty, going down 7-6 (7-4) 6-4 to Ludmilla Samsonova, while Croatian Donna Vekic knocked off seventh seed Mayar Sherif 6-4 6-1.

Six-time major champion Venus Williams played her first singles match in nearly a year but bowed out 4-6 6-1 6-4 to Rebecca Marino. 

Coco Gauff lost her second French Open final of the weekend as the teenager and Jessica Pegula were beaten by Caroline Garcia and Kristina Mladenovic in the women's doubles.

Gauff was defeated in straight sets on Saturday by world number one Iga Swiatek in her maiden grand slam final at Roland Garros.

The 18-year-old and her fellow American Pegula started well on Sunday, taking the first set before their French opponents stormed back to win 2-6 6-3 6-2 on Court Philippe-Chatrier.

An early break from Gauff and Pegula gave the number eight seeds the advantage, before another in the seventh game allowed them to serve out the opening set.

However, the experienced Garcia and Mladenovic found several more gears to race out into a 4-0 lead in the second set.

Gauff and Pegula - who was also beaten by Swiatek in the quarter-finals of the singles' event in Paris - came back to 3-4, but were broken again and the French duo grasped the chance to level the match.

The decider was one-sided, with Garcia and Mladenovic again taking a 4-0 lead, before eventually serving out to win as the 2016 champions were able to repeat the trick six years later in front of a delighted home crowd.

Mladenovic has now celebrated four doubles triumphs in her home grand slam - two with Garcia and as many with Timea Babos. This was Garcia's second success.

Iga Swiatek is enjoying a birthday week to remember – or perhaps one to forget.

The world number one turned 21 on Tuesday, between the 32nd and 33rd matches of a remarkable winning streak.

Having won five consecutive tournaments heading into the French Open, there was plenty for Swiatek to celebrate even before her big day.

So perhaps she can be forgiven for losing track of her age in the moments after her latest win against Jessica Pegula on Wednesday.

Having carried out her on-court media duties, Swiatek wrote a message on one of the Roland Garros cameras with the hashtag "#22".

"No, wait," the 21-year-old said just as she prepared to step away, covering her face with embarrassment. "I forgot how old I am!"

A failed attempt to wipe off the incorrect number resulted in Swiatek instead crossing out her message and scribbling "#21" next to it – far more untidy than any display she has turned in at Roland Garros.

Iga Swiatek showed no signs of slowing as she reached the French Open semi-finals with a straight-sets victory over Jessica Pegula, her 33rd in succession.

The 2020 Roland Garros champion entered this year's event in imperious form, having become the fourth woman this century to win five consecutive tournaments on the WTA Tour.

And the day after her 21st birthday, Swiatek took another stride towards extending that streak to six, swatting aside Pegula 6-3 6-2 in the last eight.

Only Daria Kasatkina – against whom she has won three in a row, including the second match in this remarkable run of victories – now lies between the world number one and yet another final.

The early signs were predictably ominous for Pegula as Swiatek broke immediately, although a sloppy first service game followed and saw the Pole collapse from 40-up to level the scores when she thrashed a forehand into the net cord.

Pegula then stuck with Swiatek for a period, but her opponent's class soon came to the fore again as she sensationally scrambled to beat the second bounce from a drop shot and squeeze a return over the net to restore her lead at 4-3.

That was the first of five successive Swiatek games as she wrapped up the set at the second attempt on Pegula's serve – the American committing five unforced errors in that game alone.

That sequence was interrupted by a gutsy Pegula hold, only for Swiatek to defend her own serve in the next game to remain in the ascendancy before breaking for the first time in the second with a brilliant backhand down the line.

Pegula kept battling, but she was only temporarily able to hold up Swiatek at the finish line, a seven-minute game ended by a stunning winner to break again and reach the semis.

Data Slam: Pegula no match for number one

Pegula's only previous meeting with a current number one saw her thrashed in straight sets by Ash Barty at the Australian Open. Swiatek has succeeded Barty at the top of the rankings following her retirement and has since surpassed the Aussie's dominance, now winning 16 in a row as number one.

WINNERS/UNFORCED ERRORS
Swiatek – 30/28
Pegula – 16/27

ACES/DOUBLE FAULTS
Swiatek – 4/0
Pegula – 2/1

BREAK POINTS WON
Swiatek – 5/11
Pegula – 1/2

Jessica Pegula promised to come out fighting with her "A-game" as she aims for a "great story" by defeating the in-form Iga Swiatek at the French Open.

World number one Swiatek survived a first-set scare against Zheng Qinwen in the fourth round at Roland Garros to secure a 6-7 (5-7) 6-0 6-2 win on Monday.

That extended Swiatek's winning run to 32 matches, which means only Serena Williams (34) and Venus Williams (35) have recorded longer streaks on the WTA Tour this century.

Swiatek would match the longest winning run of the 2000s – set by Venus Williams in 2000 (35) – should she go on to lift the Coupe Suzanne Lenglen for a second time on Saturday, but first has to find a way past Pegula on Wednesday.

Pegula has only dropped two sets in Paris after reaching the quarter-finals with a 4-6 6-2 6-3 triumph over Romania’s Irina-Camelia Begu.

The world number 11 was the 16th scalp of Swiatek's incredible winning run when she lost to the Pole in Miami, and the American knows she must be at her best to contend with the top seed - who turned 21 on Tuesday.

"I know I'm going to have to play really, really well," Pegula said.

"I'm going to have to play aggressive against her, I'm going to have to go for my shots, because she is better when the point extends.

"I'm going to try and shorten the points as much as I can but at the same time try and be patient and not go for too much and miss my shots.

"But it's definitely going to be really tough. Hopefully I can bring my A-game because I need it."

Pegula and Swiatek share a 1-1 head-to-head record and is determined to be the one to end her dominance. 

"I practised with her here as well before the tournament started and she's a super nice girl," Pegula revealed.

"We practised a few times. So I definitely know [her game] but obviously in the moment, it's hard to pinpoint exactly what you should do. 

"She's just been so solid in every aspect. I think it's one of those things where at least I've played her so I think I do have that familiar sense, going against her, but yeah maybe a little different on clay.

"I think it goes both ways. I think sometimes it's like, 'Oh, I wish I didn't play her in the quarter-finals. I wish I played one of the other people, and didn't meet her so early, but then at the same time, it's a great chance to have a great win and a great story."