Li Na advances to Miami Masters final with straight sets semifinal win . Defending champion beats Li Na for 15th time in a row . American will next face American Open champion Serena Williams . Men 's No . 1 Rafael Nadal sets up semifinal clash with Miami .
Serena Williams advances to Miami Masters final with straight sets semifinal win . Defending champion beats Maria Sharapova for 15th time in a row . American will next face Australian Open champion Li Na . Men 's No . 1 Rafael Nadal sets up semifinal clash with Tomas Berdych .