
Greece's Stefanos Tsitsipas reacts as he plays against Germany's Alexander Zverev during their ATP Madrid Open quarter-final tennis match at the Caja Magica in Madrid on May 10, 2019. (Photo by OSCAR DEL POZO / AFP via Getty Images)

Greece's Stefanos Tsitsipas reacts as he plays against Germany's Alexander Zverev during their ATP Madrid Open quarter-final tennis match at the Caja Magica in Madrid on May 10, 2019. (Photo by OSCAR DEL POZO / AFP via Getty Images)