Rafael Nadal maybe playing his best tennis on the grass of SW19, but the Spaniard is not expecting an easy time against Rainer Schuettler.
The 32-year-old Schuettler came through a gruelling quarter-final tie against Arnaud Clement, with the match spread over two days and lasting five hours and 12 minutes - the joint second longest tie in Wimbledon history.
And although Nadal wrapped up victory in his one-side last-eight match against Andy Murray in double quick time on Wednesday, he knows that Schuettler will pose a tough test.
Schuettler failed to qualify for Wimbledon last season, while in 2005 and 2006 he failed to make it past the first round.
But world No.2 Nadal said: "I'm going to have a difficult match against Schuettler because he is playing well.
"If he is the semi-finals, it is because he is playing very well. I don't want to think about the final. Not yet.
"I have to play very well if I want to win this tournament. I am playing well, but I don't know if it is enough. I hope so."

London calling Murray
ATP World Tour Finals Preview
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Monfils v Stepanek
Nadal v Tsonga
Djokovic v Soderling
Djokovic v Nadal
Clement v Djokovic
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