see more

NEW YORK, NEW YORK - AUGUST 28: Kei Nishikori of Japan returns a shot against Bradley Klahn of the United States during their day 3 Men's Singles match of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 28, 2019 in Queens borough of New York City. (Photo by Chaz Niell/Getty Images)

NEW YORK, NEW YORK - AUGUST 28: Kei Nishikori of Japan returns a shot against Bradley Klahn of the United States during their day 3 Men's Singles match of the 2019 US Open at the USTA Billie Jean King National Tennis Center on August 28, 2019 in Queens borough of New York City. (Photo by Chaz Niell/Getty Images)