Two-time Grand Slam champion Victoria Azarenka of Belarus has reached the third round at the French Open, while US Open champion Emma Raducanu is out in the second round.
Azarenka, seeded 15th, had only 13 unforced errors to Andrea Petkovic‘s 42 in a 6-1, 7-6 (3) win.
Nineteen-year-old Raducanu lost to Aliaksandra Sasnovich of Belarus 3-6, 6-1, 6-1 after failing to convert on five break-point chances at 1-1 in the third set.
Azarenka has twice won the Australian Open and was a semifinalist at Roland Garros in 2013.
Petkovic, 34, reached the French Open semifinals in 2014 but has not been beyond the third round at any Grand Slam since then. She is a five-time clay-court champion on the tour.
Sasnovich won 12 of 14 service points in the second set en route to her 16th career victory over a top-20 player. She advanced to the third round at Roland Garros for the first time in her seventh appearance.
Sasnovich, who is 28, had also beaten Raducanu at Indian Wells last year in the British player’s first match after winning the title at Flushing Meadows.
No. 23 Jil Teichmann advanced to the third round by defeating Olga Danilovic 6-4, 6-1.
The Associated Press contributed to this report.