Coco Gauff

NEW YORK — Coco Gauff overcame some uneven serving early in the second round of the US Open before stretching her winning streak to nine matches at the site of her first Grand Slam title with a 6-4, 6-0 victory over 99th-ranked Tatjana Maria on Wednesday night.

Gauff, a 20-year-old from Florida, had all sorts of trouble in the first set under the lights at a hot and muggy Arthur Ashe Stadium against Maria, a 37-year-old from Germany who made it to the Wimbledon semifinals two years ago and hits slices on nearly every forehand and backhand.

There were seven double-faults for defending champion Gauff in that set. She put in fewer than half of her first serves. She faced five break points, but saved four. And problems arose in other aspects of her play, too, including winning the point on just 9 of 17 trips to the net, and a total of twice as many unforced errors, 20, as winners, 10.

Her body language was frequently negative as can be after some of the mistakes. Gauff would look at her guest box and put her palms up as if to say, “What is going on?” She would roll her eyes or put a hand on a hip, including after one wild swinging volley that sailed several feet long.

When Gauff served for the opening set, she double-faulted twice and faced a pair of break points that would have allowed Maria to get the score to 5-all. But Maria missed a forehand on the first, and Gauff struck a cross-court forehand passing shot on the second, then finished off the game. 

The second set was a completely different story. 

Gauff put together 15 winners to merely five unforced errors — two of which were double-faults — and went 10 for 11 at the net.