Serena Williams, right, and Roger Federer, of Switzerland, pose for photographs during a news conference to promote the U.S. Open tennis tournament on Thursday, Aug. 27, 2009 in New York. (AP Photo/Frank Franklin II)
AP
Serena Williams poses for photographs during a news conference to promote the U.S. Open tennis tournament on Thursday, Aug. 27, 2009 in New York. (AP Photo/Frank Franklin II)
AP
Serena Williams responds to questions during a news conference to promote the U.S. Open tennis tournament Thursday, Aug. 27, 2009 in New York. (AP Photo/Frank Franklin II)
AP
Serena Williams responds to questions during a news conference to promote the U.S. Open tennis tournament Thursday, Aug. 27, 2009 in New York. (AP Photo/Frank Franklin II)
AP
Serena Williams responds to questions during a news conference to promote the U.S. Open tennis tournament, Thursday, Aug. 27, 2009, in New York. (AP Photo/Frank Franklin II)
AP
Roger Federer, of Switzerland, responds to questions during a news interview during a news conference to promote the U.S. Open tennis tournament, Thursday, Aug. 27, 2009, in New York. (AP Photo/Frank Franklin II)
AP
Roger Federer, of Switzerland, responds to questions during a news interview during a news conference to promote the U.S. Open tennis tournament, Thursday, Aug. 27, 2009, in New York. (AP Photo/Frank Franklin II)
AP
Roger Federer, of Switzerland, responds to questions during a news interview during a news conference to promote the U.S. Open tennis tournament, Thursday, Aug. 27, 2009, in New York. (AP Photo/Frank Franklin II)
AP
Tennis player Roger Federer, of Switzerland, responds to questions during a news interview during a news conference to promote the U.S. Open tennis tournament, Thursday, Aug. 27, 2009, in New York. (AP Photo/Frank Franklin II)
AP
FILE - In this Aug. 22, 2009 file photo, Rafael Nadal, from Spain, hits a backhand against Novak Djokovic, from Serbia, at the Cincinnati Open tennis tournament in Mason, Ohio. Djokovic won 6-1, 6-4. Nadal concedes he probably isn't in peak condition heading into the U.S. Open. The Spanish star returned to competition this month after taking off more than two months because of tendinitis in both knees. Now he's seeking the one major title he hasn't won. (AP Photo/Al Behrman, File)
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