Serena Williams returns the ball to China's Shuai Zhang during their match at the Italian open tennis tournament in Rome, Friday, May 16, 2014. (AP Photo/Gregorio Borgia)
Serena Williams' hand reaches for the ball as she gets ready and serve to China's Shuai Zhang, during their match at the Italian open tennis tournament in Rome, Friday, May 16, 2014. (AP Photo/Gregorio Borgia)
Serena Williams shouts after losing a point during her match against China's Shuai Zhang at the Italian open tennis tournament in Rome, Friday, May 16, 2014. (AP Photo/Gregorio Borgia)
Spain's David Ferrer returns the ball to Serbia's Novak Djokovic during their quarterfinal match at the Italian Open tennis tournament, in Rome, Friday, May 16, 2014. (AP Photo/Alessandra Tarantino)
Serbia's Novak Djokovic returns the ball to Spain's David Ferrer during their quarterfinal match at the Italian Open tennis tournament, in Rome, Friday, May 16, 2014. (AP Photo/Alessandra Tarantino)