Nadal stumbles over his move from French clay to grass

Rafael Nadal's inexperience on grass tripped him up here yesterday, literally at times, as he was ousted from the men's singles by Gilles Muller, a tournament debutant from Luxembourg.

The 19-year-old Spanish pirata, who won the French Open earlier this month, succumbed in four sets, 6-4, 4-6, 6-3, 6-4. The most telling statistic in this battle of two lefties was that the No4 seed converted only one of 13 break points.

But, as he sought to become the first man since Bjorn Borg in 1980 to win back-to back Grand Slams at Roland Garros and Wimbledon, the underlying reason was simpler still. The feat was beyond him because his feet were not. Much as he shaped, time and again, to slide into his shots, his shoes either stuck on the surface at key moments or slipped beneath him on the unfamiliar turf.

Several times he actually fell to the ground. The momentum of his body - 74kg (11st 6lb) of prime Spanish beef - overtook his legs. And because he was unable to maintain his upper body balance, he also found it harder to gain the same kind of purchase on his double-handed drives as he does on clay. In the third set, he even gaped down at the grass as if it were a strange, exotic substance.

"I think I've played OK on grass," he said. "But, as I keep saying, it is difficult to play good in all your matches. I need to improve my volley, I need to improve my serve, I need to improve my confidence on grass. And for that I need to play a lot more matches. Wimbledon will be my goal until the day that I retire."

Muller, the 22-year-old world No 69, only made it to yesterday's match because his first-round opponent, Felix Mantilla, had retired injured. Yet he produced some fine tennis to beat Nadal, setting the tone in the first game after initially falling 0-40 behind on his serve.

He recovered by unsettling Nadal with well-placed shots and then taking advantage. A smashed winner took him to 30-40, an ace took him to deuce and then errors from Nadal allowed Muller to hold. The key break in the first set came when Nadal attempted a slice that fell into the net to end the 10th game.

Nadal improved on his net approaches in the second set, which he took 6-4. But he had no answer when Muller began producing blistering passes, deft drop shots and audacious lobs to keep the Spaniard tottering. Muller, who stands 6ft 5in tall, hit 13 aces to Nadal's 11, topping 120mph on more than one occasion.

"He played a very good match," Nadal said. "He played better than me today. That happens."

Although this year is his debut in the main draw, Muller is no stranger to the All England Club, having reached the junior final here in 2001, when he also won the US Open title to finish the season ranked No 1 in the world. Last year he played Davis Cup against Britain, beating Arvind Parmar in the singles before losing to Tim Henman.

Muller now meets the French No 27 seed, Richard Gasquet.