Serena Williams and Caroline Wozniacki among those in action
Sania Mirza serves against Abigail Spears and Santiago Gonzalez as Bruno Soares looks on during the mixed doubles final of the 2014 U.S. Open tennis tournament, Friday, Sept. 5, 2014, in New York.Charles Krupa/The Associated Press
Santiago Gonzalez of Mexico and Abigail Spears of the United States play Sania Mirza of India and Bruno Soares of Brazil in the mixed doubles final on Day 12 of the 2014 U.S. Open.Streeter Lecka/Getty Images
Sania Mirza of India and Bruno Soares of Brazil play against Santiago Gonzalez of Mexico and Abigail Spears of the United States in the mixed doubles final on Day 12 of the 2014 U.S. Open at the USTA Billie Jean King National Tennis Center.Streeter Lecka/Getty Images
Bruno Soares of Brazil and Sania Mirza of India celebrate after defeating Santiago Gonzalez of Mexico and Abigail Spears of the U.S. (rear) in the mixed doubles final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.MIKE SEGAR/Reuters
Bruno Soares of Brazil and Sania Mirza of India kiss their trophy after defeating Santiago Gonzalez of Mexico and Abigail Spears of the U.S. in the mixed doubles final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.MIKE SEGAR/Reuters
Ballboys before start of the match between Caroline Wozniacki of Denmark and Peng Shuai of China, during their 2014 US Open Women's Singles - semi-finals match at the USTA Billie Jean King National Tennis Center September 5, 2014 in New York.TIMOTHY A. CLARY/AFP / Getty Images
Caroline Wozniacki, of Denmark, returns a shot against Peng Shuai, of China, during the semi-finals of the 2014 U.S. Open tennis tournament, Friday, Sept. 5, 2014, in New York.Mike Groll/The Associated Press
Peng Shuai returns a shot to Caroline Wozniacki on Day 11 of the 2014 U.S. Open tennis tournament at USTA Billie Jean King National Tennis Center.Robert Deutsch
Caroline Wozniacki hits a return to Peng Shuai during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.ADAM HUNGER/Reuters
Caroline Wozniacki of Denmark hits a return to Peng Shuai of China during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.MIKE SEGAR/Reuters
Peng Shuai returns a shot to Caroline Wozniacki on Day 11 of the 2014 U.S. Open tennis tournament.Robert Deutsch
Caroline Wozniacki of Denmark reaches for a return to Peng Shuai of China during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.ADAM HUNGER/Reuters
Peng Shuai of China serves to Caroline Wozniacki of Denmark during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.MIKE SEGAR/Reuters
Caroline Wozniacki serves against Peng Shuai during the semi-finals of the 2014 U.S. Open tennis tournament, Friday, Sept. 5, 2014, in New York.Charles Krupa/The Associated Press
Shuai Peng reacts after getting injured during her women's singles semi-final match against Caroline Wozniacki.Al Bello/Getty Images
Shuai Peng reacts after getting injured during her women's singles semi-final match against Caroline Wozniacki at the USTA Billie Jean King National Tennis Center on September 5, 2014.Michael Heiman/Getty Images
Peng Shuai is tended to after she dropped to the court in pain as her opponent Caroline Wozniacki reaches out to her during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 5, 2014.MIKE SEGAR/Reuters
Serena Williams of the United States returns a shot against Ekaterina Makarova of Russia during their women's singles semi-final match at the 2014 U.S. Open.Elsa/Getty Images
Ekaterina Makarova returns a shot against Serena Williams during their women's singles semi-final match.Elsa/Getty Images
Serena Williams returns a shot against Ekaterina Makarova during their women's singles semi-final match.Elsa/Getty Images