Maria Sharapova used 12 aces to help overcome a shaky start and reach the U.S. Open's third round.
The five-time major champion got better and better as the match wore on and came back to beat 59th-ranked Timea Babos of Hungary 6-7 (4), 6-4, 6-1 in 2 hours, 19 minutes.
Sharapova is playing in her first Grand Slam tournament since serving a 15-month doping suspension. She beat No. 2 seed Simona Halep in the first round at Flushing Meadows.
Sharapova made 19 unforced errors in the opening set against Babos, but cleaned up her play, cutting the mistakes to 12 in the second set and five in the third.