American player Anna Tatishvili has been fined her entire French Open first-round earnings of almost £41,000 for falling below the standard expected of a professional player at a Grand Slam.

Tatishvili, 29, lost 6-0 6-1 to Greek 29th seed Maria Sakkari in 55 minutes.

The former world number 50 was playing her first tour-level match since October 2017.

She used her protected ranking to enter Roland Garros.

Under International Tennis Federation rules, the match referee has the right to dock appearance money if it is felt a player used their protected ranking to play a tournament despite not being fit enough.

“All players are expected to perform to a professional standard in every Grand Slam match,” ITF rules state.

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Sloane Stephens saw off Garbine Muguruza in straight sets to set up a French Open quarter-final against British number one Johanna Konta.

Stephens, runner-up at Roland Garros last year, beat the 2016 champion 6-4 6-3 in one hour 40 minutes in Paris.

The 26-year-old seventh seed needed five match points to close out the final set on Court Philippe Chatrier.

She will now face Konta, who has beaten her twice this year including in the Italian Open third round two weeks ago.

Konta earlier defeated Croatian 23rd seed Donna Vekic 6-2 6-4 to reach her maiden quarter-final at Roland Garros and the last eight of a Grand Slam for the first time since she did so at Wimbledon in 2017.

• French Open: Britain’s Johanna Konta into quarter-finals
• Re-live Konta’s impressive victory over Vekic
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Muguruza started the brightest as she broke Stephens in her opening game of the match, with the American failing to register a point.

The 25-year-old Spaniard threatened again with five break points in the third game, but Stephens held on and responded with successive breaks of her own.

The momentum continued to switch hands as 2017 Wimbledon champion Muguruza recovered to bring it back to serve before Stephens earned the vital break and managed to close out the opening set.

Stephens, having missed an earlier chance to break, finally took the advantage in the second set as Muguruza fired a volley from close range into the net tape.

It handed the 2017 US Open champion a chance to serve for a place in the last eight, only for Muguruza to save four match points as Stephens struggled to close out.

A battling Muguruza then had a chance to break herself, but an ace from Stephens swung the game back in her favour and this time she made no mistake in closing out to seal victory.

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British number one Johanna Konta continued her charge through the French Open by impressively beating Croatian 23rd seed Donna Vekic to reach the quarter-finals.

Konta, seeded 26th, won 6-2 6-4 in baking conditions at Roland Garros.

She is hoping to emulate Jo Durie and become the first British woman to reach the semi-finals since 1983.

The 28-year-old will play 2016 champion Garbine Muguruza or Sloane Stephens – last year’s runner-up – next.

Spanish 19th seed Muguruza and American seventh seed Stephens meet on Court Philippe Chatrier later on Sunday.

“To be able to win a match like this against a tough opponent is a great feeling. I felt I played well throughout the match,” said Konta after reaching her first Grand Slam quarter-final since Wimbledon in 2017.

“To win like that in front of a crowd like that gives you goosebumps.”

Konta is enjoying a superb clay-court season, reaching WTA finals in Morocco and Rome, and has continued to build on that form in Paris with some assured performances.

She wrapped up victory over Vekic on the first of her three match points when the Croat hit long.

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Konta’s clay-court joy continues

Konta had never won a main-draw match at Roland Garros before this year and appears to be reaping the rewards of her work with coach Dimitri Zavialoff, whom she employed at the end of last year.

She is trusting her ability on a surface where she has had little previous success and against Vekic, this was again evident.

Konta produced 33 winners and seven aces on her way to victory, improving her tallies in these areas from each of her previous three matches.

Former world number four Konta was rarely flustered against Vekic, who she memorably beat in a three-set thriller on her way to the Wimbledon semi-finals two years ago.

After bouncing straight back from losing her opening service game, the Briton broke again for a 5-2 lead and kept a measure of calm to see off four break points before sealing the set with an ace down the middle.

Serve ruled at the start of the second set – with only eight receiving points won in the opening six games – before Konta struck first for a 4-3 advantage.

For the first time she wobbled as three unforced errors handed the break straight back, but she managed to reset again in the next game.

Two whopping forehands, which dusted the baseline, set the tone, forcing Vekic into a panicked backhand volley wide that brought up three break points for the Briton.

Vekic saved two of them, only for Konta to take the third when she pulled off an outrageous backhand drop shot from the back of the court.

Konta took her first match point when she expertly judged a Vekic return was going long, breaking out into a broad smile and raising both arms skywards in celebration.

“I was definitely pleased with how I was playing and the kind of problem-solving I was doing out there. I felt I was being very effective,” Konta said.

“I thought I had very few drops in my level, which I think definitely kept the pressure on her and in trying to find a solution.

“I was able to identify where I was getting points and what was making her feel uncomfortable on court. I thought I played into the open spaces quite well and was able to find opportunities to do that.”

Quarter-finals full of new faces

Konta is not alone in being a quarter-final debutant at this year’s French Open.

Croatian 31st seed Petra Martic and Czech 19-year-old Marketa Vondrousova are both in the last eight at Roland Garros for the first time and one of them will be Konta’s semi-final opponent if she is victorious in the next round.

Neither player has made it to a Grand Slam quarter-final before, but Martic reached this stage after beating Kaia Kanepi 5-7 6-2 6-4, while Vondrousova came through after a 6-2 6-0 win against 12th seed Anastasija Sevastova.

Analysis

BBC tennis correspondent Russell Fuller

Tennis can sometimes be a very simple game.

Fuelled by confidence, and playing with the utmost fluency, Johanna Konta looked in little doubt that a quarter-final spot was hers for the taking.

Konta arrived in the Moroccan capital Rabat at the end of April with some fine Fed Cup wins for GB under her belt, but a very sketchy career record on clay.

She saved three match points in the first round there, and has not looked back.

The win over Vekic was Konta’s 14th in four tournaments, and she has nothing to fear – whichever Grand Slam champion awaits in the last eight on Tuesday.

Salisbury in doubles quarter-finals

Konta was not the only Briton in action at Roland Garros, as Joe Salisbury made it to the men’s doubles quarter-finals alongside American Rajeev Ram.

The 11th seeds came back from a set down to beat eighth seeds Henri Kontinen and John Peers 3-6 6-3 7-6 (7-5).

Salisbury and Ram will face unseeded French pair Fabrice Martin and Jeremy Chardy – who was beaten by British number one Kyle Edmund in the first round of the singles – in the last eight.

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