NEW YORK, NY - AUGUST 27:  Grigor Dimitrov of Bulgaria returns a shot against Ryan Harrison of the United States during their men's singles first round match on Day Three of the 2014 US Open at the USTA Billie Jean King National Tennis Center on August 27, 2014  in the Flushing neighborhood of the Queens borough of New York City.  (Photo by Julian Finney/Getty Images)