Na Li from China serves during a Madrid Open tennis tournament match against Kirsten Flipkens from Belgium, in Madrid, Spain, Monday, May 5, 2014. (AP Photo/Andres Kudacki)
Na Li from China returns the ball during a Madrid Open tennis tournament match against Kirsten Flipkens from Belgium, in Madrid, Spain, Monday, May 5, 2014. (AP Photo/Andres Kudacki)