Serena Williams into the quarterfinals of CNN tournament in Miami . But it was more about fighting in my heart today rather than any other shot . '' Victoria Azarenka avenges 2011 U.S. Open defeat to Victoria Azarenka . World No . 1 Victoria Azarenka fights back to extend 2012 run to 26 -0 . Samantha Stosur , Maria Sharapova , Caroline Wozniacki , Venus Williams also progress .
Serena Williams into the quarterfinals of CNN tournament in Miami . Victoria Azarenka avenges 2011 U.S. Open defeat to Victoria Azarenka . World No . 1 Victoria Azarenka fights back to extend 2012 run to 26 -0 . Samantha Stosur , Maria Sharapova , Caroline Wozniacki , Venus Williams also progress .