a Sabalenka powers into US Open third round
a Stephens sends teen sensation Gauff packing
a Qualifier Zandschulp shocks eighth seed Ruud
a Medvedev makes quick work of Koepfer
a Halep scores over Kucova to advance
a Schwartzman sees off Anderson
a Osaka gets walkover.
NEW YORK: World number three Stefanos Tsitsipas fired down a career-high 27 aces on the way to a 6-3, 6-4, 6-7 (4), 6-0 win over second-round opponent Adrian Mannarino on Wednesday, but another protracted bathroom break drew jeers from the US Open crowd.
Greek Tsitsipas won all of his first-serve points in the opening set and fired off 53 winners in the match to Mannarino's 26 and looked set for a straightforward win at Arthur Ashe Stadium before the Frenchman won a third-set tiebreak.
Tsitsipas then retreated to the locker room for a bathroom break of more than seven minutes, leaving Mannarino to ask for some balls to be brought out so that he could stay loose ahead of the fourth set.
Tsitsipas, who infuriated Andy Murray in the last round by taking a seven minute-plus break, was met with a chorus of boos from spectators when he returned and even as he served to start the set.
The jeers had little impact on his performance, however, as he powered through the final six games to set up a third-round tie against Spanish teenager Carlos Alvaraz.
Tsitsipas said after the match that he was completely soaked with sweat after the third set and that important for him "to feel refreshed".
The Roland-Garros runner-up said he did not realize he had exceeded his previous career high of 22 aces in a match.
World number two Aryna Sabalenka sent Slovenian Tamara Zidansek packing in just under an hour, rolling through to the third round with a 6-3, 6-1 win.
The Belarusian broke her opponent in the first game and never ceded the momentum as Zidansek struggled with her serve, committing four double faults, and making 19 unforced errors.
Sabalenka fired off 24 winners compared to just eight from her opponent in the lopsided match, as she dominated from the baseline and made only 10 unforced errors.
It was a significant improvement from her opening match on Monday, when the Wimbledon semi-finalist beat Serbian Nina Stojanovic despite 42 unforced errors over three sets.
Sabalenka faces American Danielle Collins in the third round as she continues her bid for a maiden major title.
Experience trumped youth as former champion Sloane Stephens's deadly forehand sealed fellow-American Coco Gauff's fate 6-4, 6-2 in the second round.
The pair appeared evenly matched early in the affair but the 17-year-old Gauff handed Stephens a critical break with a double fault on the last point in the ninth game and never regained the momentum from her 28-year-old opponent.
In the second set, Gauff failed to convert on the only break point opportunity she had against the 2017 winner, who had eight forehand winners across the one hour and six minute meeting on Arthur Ashe Stadium.
Stephens calmly won the last seven points in a row, as she dominated from the baseline and had a two break advantage headed into the final game.
The off-court friends hugged at the net after the match and Stephens heaped praise on the 23rd-ranked Gauff, a fan-favourite at Flushing Meadows who reached the quarter-finals at Roland-Garros earlier this year, the best major performance of her career.
Qualifier Botic van de Zandschulp sent Norwegian eighth seed Casper Ruud packing 3-6, 6-4, 6-3, 6-4, in the biggest upset of a tournament that has so far mostly gone to script.
Ruud overcame an early break to win the first set as van de Zandschulp struggled to get his first serves in but was left without answers as the Dutchman found his form and fended off all six break point opportunities in the third.
Also exiting the tournament was 15th seeded Bulgarian Grigor Dimitrov, who retired with an injury while trailing Australian Alexei Popyrin 7-6(4), 7-6(4), 4-0.
Russian Daniil Medvedev made quick work of second-round opponent Dominik Koepfer to win 6-4, 6-1, 6-2, soaking up the cheers of the US Open crowd to keep alive his bid for a maiden Grand Slam title.
The world number two broke his German opponent's serve to kick off the match but Koepfer levelled with a break in the seventh game, helped by one of two Medvedev double faults in the opening set.
It was one of a rare few moments of vulnerability for the 25-year-old, who kicked into high gear in the second set, hitting 10 winners in a clinical performance with just five unforced errors.
Medvedev, who went from villain to crowd favourite as the runner-up in 2019, won all but one of his first-serve points in the third set and struck five aces past Koepfer, closing out victory in one hour and 48 minutes.
The pair played under Arthur Ashe Stadium's retractable roof, which was closed due to inclement weather, two years after Medvedev defeated Koepfer in the fourth round at Flushing Meadows in four sets.
The performance was encouraging for Cincinnati semi-finalist Medvedev, who picked up his fourth Masters 1000 title last month in Toronto. He faces Spain's Pablo Andujar in the third round.
You need luck to win a US Open, says Simona Halep, and she got a bit of it on Wednesday when her second-round match with Kristina Kucova was moved from a rainy outside court to the dry of Arthur Ashe Stadium, allowing her an uninterrupted 6-3 6-1 victory.
The twice Grand Slam winner missed the French Open, Wimbledon and the Tokyo Olympics due to a calf injury then, in only her second tournament back, was forced to withdraw from the US Open tune-up event in Cincinnati due to a right thigh injury.
But there were hints on Wednesday that the former world number one's luck might be changing when her match was played under the retractable roof on Arthur Ashe Stadium, filling the hole left in the schedule when Olga Danilovic withdrew due to illness, handing defending champion Naomi Osaka a walkover.
Argentine Diego Schwartzman overcame big-serving Kevin Anderson of South Africa and multiple weather interruptions to move into the third round with a 7-6 (4), 6-3, 6-4 win.
The 35-year-old Anderson, the 2017 finalist at Flushing Meadows, came into the match winning two of his previous three meetings against the 11th seeded Schwartzman.
Serve was always going to be the main weapon for the former world number five, who smashed 49 aces in Monday's opening win over Czech Jiri Vesely. He tallied another 24 against Schwartzman but was undone by unforced errors (58), tallying 37 more than his opponent. Agencies
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