WIMBLEDON, England (AP) Defending champion Rafael Nadal has reached the fourth round at Wimbledon, beating Gilles Muller in straight sets in a masterful display that keeps the Spaniard on course for a third title at the All England Club.

In a match that had been suspended after the first set Friday because of darkness, Nadal won 7-6 (6), 7-6 (5), 6-0. He committed only three unforced errors Saturday and never lost serve in the defeating the 92nd-ranked wild card from Luxembourg on Court 1.

Muller had been the last player other than Roger Federer to beat Nadal at Wimbledon, in the second round in 2005.

Nadal could next face another Grand Slam champion, 2009 U.S. Open winner Juan Martin del Potro, who was facing Gilles Simon in the third round.