
Serbia's Novak Djokovic returns the ball to Greece's Stefanos Tsitsipas during their ATP Madrid Open final tennis match at the Caja Magica in Madrid on May 12, 2019. (Photo by JAVIER SORIANO / AFP via Getty Images)

Serbia's Novak Djokovic returns the ball to Greece's Stefanos Tsitsipas during their ATP Madrid Open final tennis match at the Caja Magica in Madrid on May 12, 2019. (Photo by JAVIER SORIANO / AFP via Getty Images)