Images from the US Open women's singles second round matches, at Flushing Meadows, New York, on Wednesday.
Defending champion Coco Gauff brought her "nothing to lose" mentality to the second round of the US Open as she cleaned up early mistakes to beat unseeded German Tatjana Maria 6-4, 6-0 on Wednesday.
The American, who beat Maria in Auckland last year, roared back from an error-riddled first set to sweep through the second and close out the affair with a sublime backhand winner.
She will play 2019 semi-finalist Elina Svitolina of Ukraine in the next round.
"I have really nothing to lose," said Gauff, who credited her team with helping her stay relaxed under the pressure of the year's final major.
"I think we just treat it like practice, at the end of the day. We have fun before and after matches."
Gauff was red hot as she broke Maria in the opening game but helped her opponent to a break point with a handful of clumsy errors in the next game.
The third seed hardly had the run-up to New York that she had hoped for as she exited Toronto and Cincinnati early, and she appeared visibly frustrated at times as she put up 20 unforced errors and seven double faults in the first set.
She turned it around when she broke her opponent from the baseline in the seventh game and clawed her way back from 15-40 in the 10th.
A technical error caused the loudspeaker at Arthur Ashe Stadium to blare the word "stop," forcing the players to replay set point, but Gauff was not rattled and had a poker face as she walked back to her bench.
Maria dropped her serve with a double fault in the first game of the second set and Gauff forced the German into an error to make it 3-0, as a handful of mid-match adjustments paid off.
She started coming to the net more, catching Maria off-guard as she improved virtually every aspect of her game, running away with the match to wild applause from the home crowd.
Azarenka battles through migraine to advance
Victoria Azarenka said she suffered a migraine during her match against Clara Burel at the US Open on Wednesday but the former world number one still managed to claim a 6-1, 6-4 victory to move into the third round.
Azarenka was in cruise control as she comfortably took the opening set after winning the first five games but she quickly found herself 3-1 down in the second, appearing to struggle with the harsh lights at Louis Armstrong Stadium.
The Belarusian was in tears as she complained of a migraine and then called for the doctor, who checked her blood pressure and gave her medication during a stoppage that lasted nearly five minutes.
That took the momentum away from Burel, who made several errors after the restart as Azarenka won the next four games before sealing victory.
The 20th seed barely celebrated the win and went back to her seat to drape a towel around her head before putting on a pair of sunglasses.
"I don't know how I played the match. I just tried to, you know, hope that it's going to get better a little bit," Azarenka said in her post-match interview.
"I'm wearing glasses for a reason right now. It looks probably weird and awkward on TV. But I have a chronic migraine sometimes and it couldn't be a worse time to start it, on the match.
"It's just tough to deal with."
The twice Australian Open champion will next face China's Wang Yafan.
Sabalenka makes short work of Bronzetti
Aryna Sabalenka faced little resistance from Lucia Bronzetti as the hard-hitting Belarusian eased past the Italian 6-3, 6-1 on Wednesday to claim her spot in the US Open third round.
Sabalenka, who is one of the favourites to win the tournament, put her punishing serve to good use, pounding five aces to just one double fault while never facing a break-point.
The second-seeded Sabalenka needed a few games to settle in against the world number 76 but took control of the match when she outlasted Bronzetti in a rally to break for a 4-2 lead in the first set.
Sabalenka broke again to open the one-sided second set and cruised to the finish on a hot day at Louis Armstrong stadium.
Sabalenka, who reached the final of the tournament last year, rolled to the Cincinnati Open title earlier this month without losing a set and has yet to drop one in her two matches at Flushing Meadows so far this year.
Zheng survives Andreeva scare
Olympic champion Zheng Qinwen survived an early scare to overcome Russia's Erika Andreeva 6-7(3), 6-1, 6-2 in sweltering conditions on Wednesday to move into the third round of the US Open.
Andreeva, the elder sister of teenage sensation Mirra, had already knocked out one Chinese player in Yuan Yue and was looking to reach the third round at Flushing Meadows for the first time in her career.
Despite Andreeva taking an early lead and then clinching the tie-break, Zheng clawed her way back into the contest on the back of a solid first serve as the seventh seed finished the match with 36 winners and 20 aces.
"I started the match quite slow. Little by little I started to feel better in the reaction, in my serve," said Zheng, who was runner-up at the Australian Open this year.
"Honestly, today, I know (how) I entered the match wasn't the way I wanted but I'm glad I still fought until the end. I didn't give up, because she got a lot of chances in the second set."
Zheng started poorly, losing the first two games of the opening set and although she fought back with a break of her own, she was always playing catch-up as Andreeva surged ahead.
At 6-5 down, the Chinese number one served well to force a tie-break but a third double fault in the set gave Andreeva the upper hand and the 20-year-old Russian did not look back, sealing the set when Zheng's backhand went wide.
Zheng rediscovered her rhythm in the second set and won five games in a row from 1-1 on the strength of a superb first serve to force a decider, while Andreeva made several errors.
Andreeva's struggles continued into the third set where one of her powerful returns went so wide it was caught by a spectator behind the chair umpire while Zheng began dealing in winners and aces.
By 5-2, Andreeva had thrown in the towel and Zheng wrapped up the match with two aces to move into the third round where she will play Germany's Jule Niemeier.
Keys demolishes Maya Joint
Former finalist Madison Keys flew the American flag during the day session at Arthur Ashe Stadium, the the 14th seed trouncing Australia's Maya Joint 6-4, 6-0.
Making her 13th main-draw appearance at the US Open, Keys struck first against Joint when she converted on her third break-point opportunity for a 4-3 lead en route to wrapping up the opening set on her serve.
The 29-year-old American opened the second with another break and sprinted to the finish line in 62 minutes.
"After the first set I feel like I made a few adjustments on my returns just to put a little bit more pressure on her," said Keys, who retired from her two previous tournaments at Wimbledon and Toronto.
"And I felt like once I was able to get a little bit out ahead I really just ran with the moment and was able to close it out really well."
Up next for Keys, who lost to fellow American Sloane Stephens in the 2017 US Open final, is a clash with 33rd-seeded Belgian Elise Mertens.