France's Virginie Razzano serves during women's singles third round match against Ana Ivanovic of Serbia at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

Ana Ivanovic of Serbia returns a shot during women's singles third round match against France's Virginie Razzano at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

Ana Ivanovic of Serbia serves during women's singles third round match against France's Virginie Razzano at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

France's Virginie Razzano returns a shot during women's singles third round match against Ana Ivanovic of Serbia at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

Ana Ivanovic of Serbia jubilates during women's singles third round match against France's Virginie Razzano at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

France's Virginie Razzano returns a shot during women's singles third round match against Ana Ivanovic of Serbia at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Ivanovic won 2-0. (Xinhua/Gao Jing)

Jeremy Chardy of France serves during men's singles third round match against his compatriot Jo-Wilfried Tsonga at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France returns a shot during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France returns a shot during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France serves during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France returns a shot during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France returns a shot during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Jo-Wilfried Tsonga of France returns a shot during men's singles third round match against his compatriot Jeremy Chardy at the French Open tennis tournament at the Roland Garros stadium in Paris, France, May 31, 2013. Tsonga won 3-0. (Xinhua/Gao Jing)

Serena Williams of the United States returns the ball during the women's singles third round match against Sorana Cirstea of Romania at the French Open tennis tournament at the Roland Garros stadium in Paris May 31, 2013. Serena Williams won 2-0. (Xinhua/Gao Jing)

Serena Williams of the United States celebrates during the women's singles third round match against Sorana Cirstea of Romania at the French Open tennis tournament at the Roland Garros stadium in Paris May 31, 2013. Serena Williams won 2-0. (Xinhua/Gao Jing)