NEW YORK, NY - AUGUST 29: Gilles Muller of Luxembourg returns a shot to Gael Monfils of France during his first round Men's Singles match on Day One of the 2016 US Open at the USTA Billie Jean King National Tennis Center on August 29, 2016 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Andy Lyons/Getty Images)
