MELBOURNE, Australia (AP) — US Open champion Coco Gauff beat Marta Kostyuk 7-6 (6), 6-7 (3), 6-2 in an error-strewn match at the Australian Open on Tuesday to claim a place in the semifinals. The fourth-ranked Gauff saved two set points as she came from 5-1 down to take the opening set on the tiebreaker […]