Nadal, who was unable to defend his title at SW19 in 2009 owing to long-standing knee problems, was quick to dispel any talk of a similar injury this time around, telling reporters he had strained a muscle in his leg.

He does not believe it will be a problem going into the second week, though, where he will be looking to go on and win his 11th grand slam singles title.

“I felt the leg was a little bit more tired than usual,” the 25-year-old said after dismissing Muller, the world number 96.

“I called for the trainer and today I am still feeling it a little bit. But this is not limiting my game. I can play with it without any problems. It’s not the knee, nothing of the knee. It’s just a little bit of muscle.”

Having saved two set points during the first set, Nadal found the going no easier in the second, especially with Muller winning 95% of the points on his metronomic first serve.

But, when Nadal managed to get a racquet on one of them in the second set tie-break, he was able to engage Muller in a rally that ended with the Luxembourg player netting to put the Spaniard 2-0 up.

Muller’s resolve was broken after that and so was his serve, three times, in the next set as Nadal served out a whitewash that was an unfair reflection of Muller’s overall performance.

“Muller served fantastic during all the match in my opinion,” Nadal said.

“I was a little bit lucky in the first set yesterday because I think I only won three points before the tie-break on the return, and I had two set points against me.

“In the second set today it was very similar. But you decide the set in two balls.

“I think I played solid mentally and, in the tie-break I served all my points on the first serve. I didn’t play one point on the second. When I had the chance to return, I won the point. I think I played a good point. For that reason, I am in the third round.

“In the third set, at two sets to love, I was able to play with less pressure and I started to return unbelievably and played at a very high level, I think.”

Waiting for Nadal in Monday’s fourth round is the 2009 US Open champion Juan Martin Del Potro.

Back on the tour and back on song after a lengthy absence with a wrist injury, he is currently ranked at number 21 in the world.

A number of observers, though, including Nadal, believe him to be a lot better than that and Nadal was not particularly relishing the thought of meeting him at the midway stage of a tournament.

“It’s always a big challenge to play against him,” he said.

“He’s a very, very tough opponent, one of the best players in the world. He had an important injury last year.

“His ranking for sure is much better than what the ranking says today. His level is much better. In my opinion he’s top five. When he’s healthy he must be in the top five. He will be a tough opponent for me. I’m not lucky to play against Del Potro in the round of 16.”