PARIS -- The Latest on the French Open (all times local):
The French Open fourth-round match between seventh-seeded Kei Nishikori and unseeded Benoit Paire has been suspended due to darkness, with Nishikori leading two sets to one.
Nishikori took the first set by a 6-2 score. Paire grabbed the second 7-6 (8) before Nishikori won the third 6-2.
The players started in late evening after Stan Wawrinka's match against Stefanos Tsitsipas lasted more than 5 hours.
Play resumes on Monday, with either Nishikori or Paire to face defending champion Rafael Nadal in the last eight.
Sloane Stephens is through to the French Open quarterfinals after beating 2016 champion Garbiñe Muguruza 6-4, 6-3 of Spain on the fifth match point.
Stephens was the runner-up at Roland Garros last year, losing to Simona Halep.
After saving the fourth match point with a cross-court forehand, the 19th-seeded Muguruza hit another powerful winner to forge a break point.
But Stephens, the 2017 U.S. Open champion, saved that with an ace for deuce and moments later she was celebrating victory.
The seventh-seeded American next faces 26th-seeded Briton Johanna Konta, who won their two previous meetings.
Both those matches were played this year.
Stan Wawrinka edged Stefanos Tsitsipas 7-6 (6), 5-7, 6-4, 3-6, 8-6 after 5 hours, 9 minutes to reach the quarterfinals at a Grand Slam tournament for the first time in two years.
The 24th-seeded Wawrinka saved 22 of 27 break points, including 8 of 8 in the fifth set, against No. 6 seed Tsitsipas.
Wawrinka won the 2015 French Open for one of his three career major titles and was the runner-up in 2017. But he hadn't been past the fourth round at a Slam since, in part because he missed time after knee surgery.
He is 34, 14 years older than Tsitsipas.
Next for Wawrinka is a matchup with his friend and countryman, Roger Federer, who owns 20 Grand Slam titles. Federer leads their head-to-head series 22-3, but Wawrinka won the last time they faced each other in Paris, in the 2015 quarterfinals.
Defending champion Rafael Nadal is through to the French Open quarterfinals after beating unseeded Argentine Juan Ignacio Londero 6-2, 6-3, 6-3 in their first-ever meeting.
With Londero serving to stay in the match, the second-seeded Nadal won on his first match point with a booming forehand winner.
In reaching his 38th quarterfinal at a major, Nadal moved ahead of Roy Emerson into fourth place on the all-time list. Roger Federer leads with 54.
Nadal is aiming for a record-extending 12th French Open title — which would be the most titles by a man or woman at any major.
The 32-year-old Spaniard next faces either seventh-seeded Kei Nishikori of Japan or unseeded Frenchman Benoit Paire.
They were playing their fourth-round match later Sunday.
Roger Federer still has not dropped a set at the French Open and eased into the quarterfinals with a 6-2, 6-3, 6-3 win against unseeded Argentine Leonardo Mayer.
With temperatures reaching 88 Fahrenheit (31 Celsius) on a sun-soaked center court, the third-seeded Federer was rarely troubled in beating Mayer for the fourth time in four meetings.
After dropping his serve to lose the second set, Mayer angrily swiped the ball away and was given a code violation warning for ball abuse.
It was the second time Federer has beaten Mayer at a Grand Slam— the other also coming in straight sets, in the first round of the U.S. Open in 2015.
That was also the last year Federer played at Roland Garros, before taking the decision to skip clay entirely until returning to the surface this year.
Four years ago, Federer lost in the quarterfinals to Swiss countryman Stan Wawrinka in straight sets.
Now he could get a chance to make amends, since he next faces either Wawrinka or rising star Stefanos Tsitsipas, who beat Federer in the fourth round at this year's Australian Open.
Federer is chasing a record-extending 21st Grand Slam title. He won his only French Open in 2009.
Petra Martic has followed up her win over second-seeded Karolina Pliskova by rallying past Kaia Kanepi 5-7, 6-2, 6-4 to reach her first Grand Slam quarterfinal.
The 31st-seeded Martic had entered with an 0-4 record in the fourth round at majors — first reaching the last 16 at Roland Garros seven years ago.
The Croatian says, "I waited for this moment so, so long I don't even want to know how long."
With both players trading moon balls late in the tense third set, Martic ran down a drop shot and responded with a forehand winner up the line to break for a 5-4 lead, then converted her first match point in the next game.
Martic says, "It didn't look good at times. ... But thank God I stayed there and it paid off."
Martic next faces Vondrousova.
Also advancing was 26th-seeded Johanna Konta, who beat 23rd-seeded Donna Vekic 6-2, 6-4. Konta's quarterfinal opponent will be either 2016 champion Garbiñe Muguruza or 2017 U.S. Open champion Sloane Stephens.
While Konta had reached two Grand Slam semifinals, at the Australian Open in 2016 and at Wimbledon in 2017, she had never been past the first round at Roland Garros in four previous appearances.
Czech teenager Marketa Vondrousova has reached her first Grand Slam quarterfinal without dropping a set.
The 19-year-old Vondrousova beat 12th-seeded Anastasija Sevastova 6-2, 6-0 in just 59 minutes.
The only two games that Vondrousova lost came immediately after she took a medical timeout to receive treatment for an apparent cut on a finger of her left hand — her playing hand — while leading 3-0 in the first. She appeared to pick up the cut when Vondrousova slipped and fell to the clay in the previous game.
Vondrousova tells the crowd, "I think I played my best tennis today."
With the temperature rising to nearly 85 Fahrenheit (29 Celsius), both players put towels containing ice packs around their necks during the changeovers.
Vondrousova improved to 25-5 since exiting the Australian Open in the second round — a stretch that includes finals in Budapest and Istanbul.
For a spot in the semifinals, Vondrousova will face either 31st-seeded Petra Martic or Kaia Kanepi.
Only three of the 16 women still in the French Open field have won a Grand Slam tournament — and two of them play each other in the fourth round.
The most intriguing matchup at Roland Garros on Sunday might just be 2017 U.S. Open champion Sloane Stephens against two-time major champ Garbiñe Muguruza, which is scheduled to wrap up the schedule at Court Philippe Chatrier.
Muguruza's first Slam title came in Paris in 2016, while Stephens was the runner-up a year ago against Simona Halep, who is on the other side of the draw.
In men's action on Day 8, Rafael Nadal faces 78th-ranked Juan Ignacio Londero, and Roger Federer meets 68th-ranked Leonardo Mayer.
Neither Londero nor Mayer, both from Argentina, ever has played in the round of 16 at the French Open. Indeed, Londero is making his Grand Slam debut.
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