Serena Williams of the USA waves after her tennis match against Angelique Kerber of Germany during the WTA championship in Istanbul, Turkey, Tuesday, Oct. 23, 2012. (AP Photo)

 

              Serena Williams of the USA waves after her tennis match against Angelique Kerber of Germany during the WTA championship in Istanbul, Turkey, Tuesday, Oct. 23, 2012. (AP Photo)
Serena Williams of the USA waves after her tennis match against Angelique Kerber of Germany during the WTA championship in Istanbul, Turkey, Tuesday, Oct. 23, 2012. (AP Photo)
Tags: Germany , USA