Germany's Angelique Kerber celebrates after defeating Madison Keys of the United States in their third-round match at the Australian Open tennis championship in Melbourne, Australia, on Friday, Jan. 18, 2013. (AP Photo/Dita Alangkara)

Photo by: Dita Alangkara

Germany's Angelique Kerber celebrates after defeating Madison Keys of the United States in their third-round match at the Australian Open tennis championship in Melbourne, Australia, on Friday, Jan. 18, 2013. (AP Photo/Dita Alangkara)