Hyeon Chung Pictures
NEW YORK, NY - AUGUST 30: Hyeon Chung of South Korea looks on during his men's singles second round match against Mikhail Kukushkin of Kazakhstan on Day Four of the 2018 US Open at the USTA Billie Jean King National Tennis Center on August 30, 2018 in the Flushing neighborhood of the Queens borough of New York City. (Photo by Al Bello/Getty Images)