2016 US Open champion Angelique beat Anna-Lena Friedsam 6-3, 7-6 (6) on Wednesday to reach the third round at Flushing Meadows.
Angie, a three-time Grand Slam titlist, traded breaks once with her German compatriot, before breaking again in the sixth game to grab a one-set lead.
She opened the second set with another break, but Friedsam responded immediately to level. The 17th-seed converted her second match point in a tie-breaker, improving to a perfect 3-0 record over her rival.
The match at Louis Armstrong Stadium lasted one hour and 40 minutes.
Match statistics: aces (1-2), double faults (1-2), winners (19-28), unforced errors (17-28), total points won (73-69).
For a place in the last 16, Angelique will meet either no.13 seed Alison Riske (USA) or Ann Li (USA).