Serena Williams reacts after beating Victoria Azarenka, of Belarus, in the championship match at the 2012 US Open tennis tournament, Sunday, Sept. 9, 2012, in New York. Two points from defeat, Williams suddenly regained her composure to come back and win the last four games, beating No. 1-ranked Azarenka 6-2, 2-6, 7-5 on Sunday for her fourth U.S. Open title and 15th Grand Slam title overall. (AP Photo/Mike Groll)
Serena Williams reacts after beating Victoria Azarenka, of Belarus, in the championship match at the 2012 US Open tennis tournament, Sunday, Sept. 9, 2012, in New York. Two points from defeat, Williams suddenly regained her composure to come back and win the last four games, beating No. 1-ranked Azarenka 6-2, 2-6, 7-5 on Sunday for her fourth U.S. Open title and 15th Grand Slam title overall. (AP Photo/Mike Groll)
Serena Williams reacts after beating Victoria Azarenka, of Belarus, in the championship match at the 2012 US Open tennis tournament, Sunday, Sept. 9, 2012, in New York. (AP Photo/Mike Groll)
Novak Djokovic of Serbia reacts while playing Spain's David Ferrer during a semifinal match at the 2012 US Open tennis tournament, Sunday, Sept. 9, 2012, in New York. (AP Photo/Mike Groll)
Novak Djokovic of Serbia reacts while playing Spain's David Ferrer during a semifinal match at the 2012 US Open tennis tournament, Sunday, Sept. 9, 2012, in New York. (AP Photo/Mike Groll)
Britain's Andy Murray adjusts his cap while playing Czech Republic's Tomas Berdych during a semifinal match at the 2012 US Open tennis tournament, Saturday, Sept. 8, 2012, in New York. (AP Photo/Mike Groll)
Britain's Andy Murray adjusts his cap while playing Czech Republic's Tomas Berdych during a semifinal match at the 2012 US Open tennis tournament, Saturday, Sept. 8, 2012, in New York. (AP Photo/Mike Groll)
The tennis court at Arthur Ashe stadium is shown as rain falls before play is to resume at the 2012 US Open tennis tournament, Saturday, Sept. 8, 2012, in New York. (AP Photo/Charles Krupa)
The tennis court at Arthur Ashe stadium is shown as rain falls before play is to resume at the 2012 US Open tennis tournament, Saturday, Sept. 8, 2012, in New York. (AP Photo/Charles Krupa)
