2016 U.S. Open Tennis Tournament. New York. USA. [Getty Images]

2016 U.S. Open - Day 8 Serena Williams of the United States in action against Yaroslava Shvedova of Kazakhstan in the Women's Singles round four match on Arthur Ashe Stadium on day eight of the 2016 US Open Tennis Tournament at the USTA Billie Jean King National Tennis Center on September 5, 2016 in Flushing, Queens, New York City. (Photo by Tim Clayton/Corbis via Getty Images)

Corbis Sport Tim Clayton - Corbis