Serena Williams, seen here during the final of the BNP Paribas Open in Indian Wells, Calif., responded to comments by the tourney's director, saying, "Last year, the women's final at the U.S. Open sold out well before the men. I'm sorry, did Roger play in that final, or Rafa or any man play in that final that was sold out before the men's final?" Robyn Beck/AFP/Getty Images hide caption

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Serbia's Novak Djokovic has won the Australian Open six times — in 2008, 2011, 2012, 2013 and 2015, and then on Sunday. William West/AFP/Getty Images hide caption

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Actually, he loves charity work: Filmmaker (and charity activist) Richard Curtis (left) poses with U.N. Secretary-General Ban Ki-moon and his special adviser Amina J. Mohammed. Kena Betancur/Getty Images for Global Goals hide caption

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Serena Williams returns a shot to Venus Williams during Tuesday's quarterfinals match of the 2015 U.S. Open in New York City. Matthew Stockman/Getty Images hide caption

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Sisters Serena, left, and Venus Williams shake hands after a match in 1991 in Compton, Calif. Paul Harris/Getty Images hide caption

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Before Superstardom, Williams Sisters Stunned On Compton's Courts
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Serena Williams en route to winning the Western & Southern Open in Cincinnati on Sunday. Tannen Maury/EPA/Landov hide caption

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What If Serena Williams Had Faced Tougher Rivals?
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Serena Williams serves the ball to Andrea Hlavackova during the first round of the French Open in Paris. Christophe Ena/AP hide caption

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For Sports Immortality, The 3rd Or 4th Time's The Charm
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World No. 1 Serena Williams acknowledges the crowd after winning her match against Monica Niculescu of Romania during the BNP Paribas Open at Indian Wells Tennis Garden in Indian Wells, Calif. Charls Baus/CSM /LANDOV hide caption

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Serena Williams holds up the championship trophy after defeating Victoria Azarenka, of Belarus, during the women's singles final of the 2013 U.S. Open tennis tournament on Sunday in New York. David Goldman /AP hide caption

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Defending champion Serena Williams lost to Sabine Lisicki of Germany 6-2 1-6 6-4 in the fourth round of the Wimbledon Championships. Andy Rain/EPA /Landov hide caption

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