BELGRADE, SERBIA - 23. APRIL: Taro Daniel of Japan returns the ball during the quarterfinals match against Federico Delbonis of Argentina at Novak Tennis Centre on April 23, 2021 in Belgrade, Serbia. (Photo by Srdjan Stevanovic/Getty Images)
BELGRADE, SERBIA - 23. APRIL: Taro Daniel of Japan returns the ball during the quarterfinals match against Federico Delbonis of Argentina at Novak Tennis Centre on April 23, 2021 in Belgrade, Serbia. (Photo by Srdjan Stevanovic/Getty Images)