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...