NEW YORK, NY - SEPTEMBER 03: Stan Wawrinka of Switzerland returns a shot against Kei Nishikori of Japan during their men's singles quarterfinal match on Day Ten of the 2014 US Open at the USTA Billie Jean King National Tennis Center on September 3, 2014 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Streeter Lecka/Getty Images)
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