Novak Djokovic of Serbia reacts after winning the first set against Tomas Berdych of the Czech Republic in the men's singles semifinal match at the Shanghai Masters tennis tournament at Qizhong Forest Sports City Tennis Center in Shanghai, China, Saturday Oct. 13, 2012. (AP Photo/Eugene Hoshiko)

Associated Press
Novak Djokovic of Serbia reacts after winning the first set against Tomas Berdych of the Czech Republic in the men's singles semifinal match at the Shanghai Masters tennis tournament at Qizhong Forest Sports City Tennis Center in Shanghai, China, Saturday Oct. 13, 2012. (AP Photo/Eugene Hoshiko)
Novak Djokovic of Serbia reacts after winning the first set against Tomas Berdych of the Czech Republic in the men's singles semifinal match at the Shanghai Masters tennis tournament at Qizhong Forest Sports City Tennis Center in Shanghai, China, Saturday Oct. 13, 2012. (AP Photo/Eugene Hoshiko)