U.S. Open 2013 (96 images)

Caroline Wozniacki of Denmark reacts after winning a point in her straight sets second round victory over Chanelle Scheepers of South Africa in Arthur Ashe Stadium on day four at the U.S. Open Tennis Championships at the USTA Billie Jean King National Tennis Center in New York City on August 29, 2013. UPI/John Angelillo

David Ferrer of Spain returns the ball to Roberto Bautista Agut, also from Spain, in the fourth set of round-two action at the U.S. Open Championship held at the USTA Billie Jean King National Tennis Center on August 29, 2013 in New York City. Ferrer won 6-3, 7-6,6-1, 6-2. UPI Photo/Monika Graff

Mike Bryan (L) and his brother Bob (USA) take on Federico Delbonis and Leonardo Mayer of Argentina in the first-round doubles match at the U.S. Open Championship held at the USTA Billie Jean King National Tennis Center on August 29, 2013 in New York City. UPI Photo/Monika Graff

Galina Voskoboeva of Kazakhstan misses a serve by Serena Williams (USA) in the first set during round-two action at the U.S. Open Championship held at the USTA Billie Jean King National Tennis Center on August 29, 2013 in New York City. UPI Photo/Monika Graff