Maria Sharapova battled to reach the third round of the US Open while in the men's section Alexander Zverev and Nick Kyrgios crashed out.
Sharapova, who downed second-ranked Simona Halep in her first Grand Slam match after a 15-month doping ban, defeated Hungary's 59th-ranked Timea Babos 6-7 (4/7), 6-4, 6-1 at Arthur Ashe Stadium. (AFP)
"I felt like going into the match I just wanted to get it done," Sharapova said.
"It wasn't my best tennis. It was scrappy tennis but sometimes those kind of matches are a lot of fun and this was one of those days."
The 30-year-old Russian became the first player into the third round where she will face Russian-born US teen wildcard Sofia Kenin.
Sharapova, whose five Grand Slam titles include the 2006 US Open, tested positive for meldonium at the 2016 Australian Open, her most recent Grand Slam appearance (AFP)
Kyrgios, the 14th seed and highest-ranked obstacle in Federer's quarter-final path, hurt his right shoulder in a 6-3, 1-6, 6-4, 6-1 first-round loss to 235th-ranked Aussie John Millman.
"Early in the third set I hit one serve and I never felt the same after that," Kyrgios said. "Something didn't feel right in my arm."
Kyrgios, 22, beat Rafael Nadal two weeks ago on the way to the biggest final of his career at the ATP Cincinnati Masters before falling to Grigor Dimitrov. (AFP)
Germany's fourth-seeded Alexander Zverev was knocked out in the second round of the US Open on Wednesday, falling to Croatia's Borna Coric 3-6, 7-5, 7-6 (7/1), 7-6 (7/4). (AFP)
Zverev, whose five ATP titles this year included a win over Roger Federer in the Montreal final earlier this month, had been the highest-ranked player in his half of the draw. (AFP)
France's Jo-Wilfried Tsonga returns serve against Canada's Denis Shapovalov. (AFP)
France's Jo-Wilfried Tsonga serves during his match against Canada's Denis Shapovalov. (AFP)