X
WATCH & READ
Who will win the US Open on both sides?
0:33
Loading
New York -- Roberta Vinci fell apart after losing the opening set on a foot fault, allowing No. 2 seed Angelique Kerber to take last nine games and win their U.S. Open quarterfinal 7-5, 6-0 on Tuesday.
Kerber, who has a chance to overtake Serena Williams at No. 1 after the tournament, moved into her third Grand Slam semifinal of the year. She won the Australian Open in January, then lost to Williams in the Wimbledon final in July.