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Federer surprised by Nadal's workload

Reigning Wimbledon champion Roger Federer said he understands Rafael Nadal's decision to withdraw from the Gerry Weber Open after playing "surprisingly often" in the build-up to his French Open triumph.

But the world No. 3 added that his success on the grass courts of the All England Club owed a lot to playing his traditional warm-up event in Halle.

Nadal claimed a record eighth title at Roland Garros, his first grand slam tournament since a seven-month injury lay-off in 2012 to deal with chronic tendinitis in his left knee.

The world No. 5 has reached the final of all nine of the tournaments he has played since his comeback, winning seven. He was due to join Federer in Halle but pulled out of the tournament on the advice of his medical team.

Nadal will now head to Wimbledon without having played a competitive match on grass since his shock second-round exit at the hands of Lukas Rosol in 2012.

"Obviously you can't always prepare yourself optimally," Federer said. "We don't know the extent of Rafael Nadal's problem with his knee well enough to judge why he's withdrawn here.

"He has played surprisingly often since returning to the tour, so a break is rather obvious, otherwise he will be out of action for another six months, as he was before.

"I believe it is a well thought out decision. It's obviously disappointing for the fans in Halle, but it's part of tennis."

Federer returns to Wimbledon as defending champion, but the 17-time grand slam champion is all too aware of the pitfalls of poor preparation before arriving at SW19.

"I always come to Wimbledon highly motivated - I have achieved so much there, and I always have the feeling that you can achieve a lot," Federer continued. "But I have also realised that you have to feel good - if you don't feel good about what you are doing defeats can happen very fast on the grass.

"You shouldn't question yourself and play with self-confidence. That self-confidence is there, but victories in Halle would help me a lot. That's why, with one eye on Wimbledon, the Halle tournament is very important for me."

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