Belarus' Victoria Azarenka displays the trophy, after her victory against Serena Williams of the US, in the final match of the Qatar WTA Ladies Open tennis tournament, in Doha, Qatar, Sunday, Feb. 17, 2013. (AP Photo/Osama Faisal)
Belarus' Victoria Azarenka displays the trophy, after her victory against Serena Williams of the US, in the final match of the Qatar WTA Ladies Open tennis tournament, in Doha, Qatar, Sunday, Feb. 17, 2013. (AP Photo/Osama Faisal)
Victoria Azarenka of Belarus kisses her trophy after winning the women's final against China's Li Na at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 26, 2013. (AP Photo/Andy Wong)
Victoria Azarenka of Belarus kisses her trophy after winning the women's final against China's Li Na at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 26, 2013. (AP Photo/Andy Wong)
Victoria Azarenka of Belarus waves to the crowd after winning her semifinal match against Sloane Stephens of the US at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 24, 2013. (AP Photo/Andrew Brownbill)
Victoria Azarenka of Belarus waves to the crowd after winning her semifinal match against Sloane Stephens of the US at the Australian Open tennis championship in Melbourne, Australia, Thursday, Jan. 24, 2013. (AP Photo/Andrew Brownbill)
FILE - In this Nov. 4, 2012, file photo, Serena Williams of the U.S. returns a serve from sister Venus during an exhibition tennis match at Ellis Park Indoor Arena in Johannesburg, South Africa. Williams has had surgery on her big toes and withdrew from an exhibition match against top-ranked Victoria Azarenka in Thailand in December. A medical certificate from Florida podiatrist Jeffrey Rockefeller says Williams "was treated for a chronic foot disorder which involved minor procedures on both of her great toes." (AP Photo/Themba Hadebe, File)
FILE - In this Nov. 4, 2012, file photo, Serena Williams of the U.S. returns a serve from sister Venus during an exhibition tennis match at Ellis Park Indoor Arena in Johannesburg, South Africa. Williams has had surgery on her big toes and withdrew from an exhibition match against top-ranked Victoria Azarenka in Thailand in December. A medical certificate from Florida podiatrist Jeffrey Rockefeller says Williams "was treated for a chronic foot disorder which involved minor procedures on both of her great toes." (AP Photo/Themba Hadebe, File)
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)
