NEW YORK (AP) — The Latest on the U.S. Open tennis tournament (all times local):
Maria Sharapova overcame a bit of a stumble and 10 double-faults to grab the last three games in a 6-2, 7-5 victory over 51st-ranked Sorana Cirstea of Romania 6-2, 7-5 in the U.S. Open's second round.
Five-time major champion Sharapova got broken at love to trail 5-4 in the second set. Cirstea then served to force a third set, and was two points away from doing so at 30-15, but Sharapova broke there to start her match-ending run.
Next up for Sharapova is a third-round matchup against 2017 French Open champion Jelena Ostapenko.
No. 2 seed Caroline Wozniacki is out of the U.S. Open in the second round, joining No. 1 Simona Halep on the sideline.
Wozniacki lost 6-4, 6-2 to 36th-ranked Lesia Tsurenko of Ukraine.
Wozniacki is the reigning Australian Open champion and twice was the runner-up at Flushing Meadows, in 2009 and 2014. But she's now lost in the second round at two consecutive majors, after doing the same at Wimbledon.
Her loss means the U.S. Open's top two women already are gone after only four days of action; Halep lost on Monday. A third top-10 seed lost, too: No. 9 Julia Goerges.
Tsurenko has never been past the fourth round at any Grand Slam tournament. She appeared to hurt her right forearm early in Thursday night's match, and a trainer came out to massage Tsurenko at changeovers.
Novak Djokovic wasted a match point in the third set, before going on to win 6-1, 6-3, 6-7 (2), 6-2 against Tennys Sandgren at the U.S. Open to reach the third round.
Djokovic had a much easier victory over Sandgren, an American ranked 61st, in Wimbledon's first round this year, dropping only six games in all.
The 13-time major champion seemed to be along the same path at Flushing Meadows on Thursday night, standing one point from victory while leading 5-4 in the third set as Sandgren served at 30-40. But Sandgren ended an 11-stroke exchange with a forehand winner, then took the ensuing tiebreaker.
Djokovic regained the upper hand with an early break in the fourth and was on his way.
In a U.S. Open matchup between two young, up-and-coming men in the top 50, 19-year-old Alex de Minaur beat 20-year-old Frances Tiafoe 6-4, 6-0, 5-7, 6-2 to reach the third round at a second Grand Slam tournament in a row.
Tiafoe, an American, is ranked 44th, one spot ahead of de Minaur, an Australian. Both made it to the third round at Wimbledon this year.
Tiafoe compared de Minaur to a "backboard" and acknowledged that he "lost my head" in the second set.
Tiafoe ended up with 51 unforced errors, 18 more than de Minaur.
Gael Monfils retired in the second set of his second-round U.S. Open match against 2014 runner-up Kei Nishikori because of an injured right wrist.
The 39th-ranked Monfils, a semifinalist at Flushing Meadows two years ago, was treated by a trainer and had his wrist taped up. But he unraveled the tape shortly before saying he could not continue.
The Frenchman was trailing 6-2, 5-4 when he stopped.
Pablo Carreno Busta was unable to duplicate his U.S. Open run from a year ago, forced to retire from his second-round match because of left thigh pain.
Carreno Busta reached the semifinals last year in Flushing Meadows.
Joao Sousa of Portugal led Carreno Busta 4-6, 6-3, 5-7, 6-2, 2-0 when the No. 12 seed from Spain had to stop playing.
The U.S. Open and the Grand Slam Board will review chair umpire Mohamed Lahyani's interaction with Nick Kyrgios during a second-round match.
Tournament referee Brian Earley says Lahyani took the unusual step of climbing out of his chair to speak with Kyrgios "to make sure he could communicate effectively" because of noise in the arena. Earley says Kyrgios was told by Lahyani that the chair umpire "would need to take action" if Kyrgios' "seeming lack of interest in the match continued."
According to Early, Lahyani "was concerned that Kyrgios might need medical attention."
U.S. Tennis Association spokesman Chris Widmaier says that Early and the tournament's chief umpire, Soeren Frienel, are still reviewing the episode.
Make it 18 for 18 for Roger Federer in the second round of the U.S. Open.
The No. 2 seed beat Benoit Paire 7-5, 6-4, 6-4 to continue his streak of reaching the third round in the tournament he has won five times.
Federer will next face No. 30 seed Nick Kyrgios.
Federer is 7-0 against Paire, winning 16 of 17 sets against the Frenchman.
Madison Keys cruised into the third round of the U.S. Open, beating fellow American Bernarda Pera 6-4, 6-1.
The U.S. Open runner-up last year served eight aces and never lost her serve in the match that lasted 1 hour, 12 minutes.
The No. 14 seed will play either Aleksandra Krunic or Kirsten Flipkens in the next round.
No. 14 seed Fabio Fognini of Italy was upset in the U.S. Open's second round by 55th-ranked John Millman of Australia 6-1, 4-6, 6-4, 6-1.
By reaching the third round, Millman equaled his best showing at any Grand Slam tournament.
Fognini, the husband of 2015 U.S. Open champion Flavia Pennetta, was kicked out of the U.S. Open doubles tournament last year after vulgarly insulting a female chair umpire during a first-round loss in singles.
After an unusual visit from the chair umpire, Nick Kyrgios turned around his match and won it to reach the U.S. Open's third round.
Kyrgios was down a set and 3-0 in the second when official Mohamed Lahyani climbed down from his seat and went over to speak to the player — something rarely, if ever, seen during a professional tennis match. At one point, Lahyani said, "I want to help you."
The No. 30-seeded Kyrgios, who once was suspended by the ATP men's tour after not trying during a match, started playing better and eventually beat Pierre-Hugues Herbert of France 4-6, 7-6 (6), 6-3, 6-0.
Alexander Zverev has finally reached the third round of the U.S. Open.
The No. 4 seed beat Nicolas Mahut 6-4, 6-4, 6-2 for his best result in the year's final Grand Slam tournament.
Zverev had been knocked out in the second round in his three previous appearances.
Three-time major champion Angelique Kerber got through a second-round test at the U.S. Open, edging 82nd-ranked Johanna Larsson of Sweden 6-2, 5-7, 6-4.
Kerber moved ahead in a third set filled with lengthy baseline exchanges by breaking in the next-to-last game when Larsson double-faulted.
The No. 4-seeded Kerber won the U.S. Open in 2016. Her other Grand Slam trophies came at that year's Australian Open and this year's Wimbledon.
The Williams sisters will lead off the night session at Arthur Ashe Stadium on Friday with their third-round showdown at the U.S. Open.
It will be the 30th tour-level meeting between Venus and Serena, but the earliest at a Grand Slam since Venus won a second-round matchup at the 1998 Australian Open. That was the first time they played each other as pros.
Venus is the No. 16 seed, one spot above her younger sister. They have twice met in the U.S. Open final, trading victories in 2001 and 2002.
They will be followed on Ashe by 2009 champion Juan Martin del Potro against Spain's Fernando Verdasco.
The Belarussians are coming.
Aliaksandra Sasnovich and Aryna Sabalenka have won second-round matches at the U.S. Open, continuing Belarus' top performance in a major.
With former No. 1 Victoria Azarenka and Vera Lapko also winning their first matches at Flushing Meadows, Belarus had four players reach the second round of a Grand Slam for the first time.
Azarenka had already reached the third round and was joined by the 33rd-ranked Sasnovich, who upset No. 11 seed Daria Kasatkina 6-2, 7-6 (3), and No. 26 seed Sabalenka, who ousted Vera Zvonareva 6-3, 7-6 (7).
Azarenka faces defending champion Sloane Stephens in the third round Friday. Lapko was eliminated by 15th-seeded Elise Mertens on Wednesday.
The extreme heat policy is in effect for the third straight day at the U.S. Open.
A 10-minute break will be allowed between the second and third sets of women's singles matches if either player requests one. For men's singles matches, the break would come between the third and fourth sets.
U.S. Open officials began the policy, which is a rule on the women's tour but not the men's, on Tuesday, when temperatures first soared into the mid-90s. It was 86 degrees (30 Celsius) just before Thursday's day session on Arthur Ashe Stadium was to begin.
The Open says the policy will remain until further notice.
The first two rounds of the U.S. Open have always been a breeze for Roger Federer.
Alexander Zverev is still trying to master them.
Federer tries to remain unbeaten in the first two rounds at Flushing Meadows, and Zverev finally tries to make the third round for the first time when both are in action Thursday.
Former champions Novak Djokovic and Maric Cilic also have second-round matches on the men's side, and 2016 champ Angelique Kerber is among the women in action.
Federer, 17-0 in second-round matches, faces Frenchman Benoit Paire. The No. 2 Federer has won all six meetings, though Paire had two match points in their last matchup in June in Germany before the five-time U.S. Open champion won 9-7 in a third-set tiebreaker.
Zverev, the No. 4 seed, is in the U.S. Open for the fourth time. He faces another Frenchman, Nicolas Mahut.
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