Rafael Nadal vs Gilles Simon Australian Open 2009 Grand Slam

Nadal, who now faces an easier route to the final following Andy Murray’s shock defeat against Fernando Verdasco, has yet to drop a set at Melbourne Park.

Nadal dominated the 2007 finalist 6-3, 6-2, 6-4 to advance to a last-eight clash with France's Gilles Simon as he seeks his first hard-court Grand Slam win.

The Spaniard, capitalising on Gonzalez's four-hour marathon with Richard Gasquet, raced through the first two sets in less than 40 minutes each, pushing the 13th seed back to keep his giant forehand at bay.

Gonzalez mounted a brief revival in the third but Nadal hit back from 3-0 down and got the decisive break 4-3 with a forehand into the corner.

The Wimbledon and French Open champion, looking fit and revived after an extended off-season, is yet to be challenged after easy wins against Christophe Rochus, Roko Karanusic and Tommy Haas.

His victory also avenges his quarter-final loss two years ago to Gonzalez, whom he also beat in the Beijing Olympic final in August.

Simon booked his meeting with Nadal when ailing friend and fellow Frenchman Gael Monfils withdrew with a wrist injury while losing 6-4, 2-6, 6-1.

Monfils, the 12th seed, began to struggle during the third set when he started taking his right hand off the racket every time he played a shot.

At 1-4 down he had a medical time-out while a trainer looked at his wrist, but he continued, only to lose the third set 6-1.

He came out for the start of the fourth but decided he couldn't go on and withdrew.

"It happened during the game slowly," Monfils said.

"Then like when I really felt it when it was at 3-1 for Gilles (in the third set).

"I mean, it was maybe 3-0 on my serve, that service game, then I start to feel it like very heavy.

"Then I asked the physio. I was thinking maybe it was in my head. Then I say, I feel it. I ask the physio and finish."

Both players know each other very well and it was apparent they were not playing their normal games.

"I can't win against him if I just play my game as usual, because he really likes to run right, left, right, left, every time," Simon said.

"It's just useless against him. That's why I just wanted to play slower than usual, just to try to attack then, because I wanted to change the pace.

"But, well, we just want to win the match, so I did what I had to do."