Nadal, Federer in Madrid quarterfinal

Rafael Nadal and Roger Federer reached the Madrid Open quarter-finals with contrasting victories.



Spanish world number two, Nadal, came through a tricky encounter against big-serving American, John Isner, 7-5, 6-4.



In the late match, top seed Federer had an easier time in seeing off fellow Swiss, Stanislas Wawrinka, 6-3, 6-1.



Nadal\'s countryman, sixth seed Fernando Verdasco, a semi-finalist at the Rome Masters, suffered a surprise 7-5, 6-3 loss to Austrian Jurgen Melzer.



Nadal now faces French 12th seed Gael Monfils, a 7-6, 6-4 winner over Guillermo Garcia-Lopez.



Federer faces Latvian Ernests Gulbis, who beat Feliciano Lopez 6-2, 7-6.