Taylor Townsend, of the U.S, returns the ball to Spain's Carla Suarez Navarro during their third round match of the French Open tennis tournament at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/David Vincent)
Spain's Garbine Muguruza returns the ball to Slovakia's Anna Schmiedlova during their third round match of the French Open tennis tournament at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/Darko Vojinovic)
France's Gilles Simon grimaces after missing a return during the third round match of the French Open tennis tournament against Canada's Milos Raonic at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/Michel Euler)
Canada's Milos Raonic returns the ball to France's Gilles Simon during the third round match of the French Open tennis tournament at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/Michel Euler)
Canada's Milos Raonic serves the ball during the third round match of the French Open tennis tournament against France's Gilles Simon at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/Michel Euler)
Serbia's Novak Djokovic returns the ball during the third round match of the French Open tennis tournament against Croatia's Marin Cilic at the Roland Garros stadium, in Paris, France, Friday, May 30, 2014. (AP Photo/David Vincent)
Sloane Stephens of the U.S. wipes beads of perspiration during the second round match of the French Open tennis tournament against Slovenia's Polona Hercog at the Roland Garros stadium, in Paris, France, Thursday, May 29, 2014. (AP Photo/Michel Spingler)
CORRECTING WINNER'S FIRST NAME TO ANA - Serbia's Ana Ivanovic returns the ball during the second round match of the French Open tennis tournament against Ukraine's Elina Svitolina at the Roland Garros stadium, in Paris, France, Thursday, May 29, 2014. (AP Photo/Darko Vojinovic)