Serves

Issei Kato/Reuters

Switzerland’s Roger Federer serves during his Men’s singles first round match against Austria’s Jurgen Melzer at The Australian Open. Photo Issei Kato/Reuters

Stephens of U.S. serves during her match against Wozniacki of Denmark at China Open tennis tournament in Beijing...Sloane Stephens of the U.S. serves during her match against Caroline Wozniacki of Denmark at the China Open tennis tournament in Beijing October 3, 2013.  REUTERS/Petar Kujundzic

Petar Kujundzic/Reuters

Sloane Stephens of the US serves during her match against Caroline Wozniacki of Denmark at the China Open tennis tournament in Beijing.