Last year's US Open finalist Madison Keys recovered from a set down to beat Serbia's Aleksandra Krunic 4-6 6-1 6-2 and reach the last 16 in New York.
The American was broken in her first service game of the match en route to losing the first set but broke twice in the second to take it to a decider.
The first five games of the third set went against serve before the American held for 4-2 and closed out the match.
The 14th seed was beaten by compatriot Sloane Stephens in last year's final.
She will face 29th seed Dominika Cibulkova or Wimbledon champion Angelique Kerber, the fourth seed, in the next round.