Defending champion 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 .
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 .