Nadal makes transition from clay to grass look easy with straight sets cruise

Spain's Rafael Nadal returns the ball to Swede Jonas Bjorkman during their match at Queen's club

"I'm very happy to be here for the third time," said the top seeded Spaniard, who will face Japanese teenager Kei Nishikori in the last 16.

 "I'm here to try my best. Right now, I am playing well but it's very difficult to adapt from clay to grass. It is always a pleasure to play on grass.

"For sure the first day, the sensation is a little bit strange. But the most important thing is I have one match already played. For the first day, it was good for me.

"For sure, this tournament is very important. If I can have a very good result here, it is going to be very important for me.  But if I play some matches, that's the most important thing, to prepare well for Wimbledon.

"The important thing is to arrive there playing well. It's going to be very important the first matches. If you can win the first two, three matches, later is a little bit easier, especially if there is sun, it will be easier because the court is a little bit more tougher, a little bit more easy for me to play.

"I know the grass is a difficult surface for me, but probably I play my best tennis on this surface, too.

"Wimbledon is a very important tournament, but for me it's important to improve on every surface. I am still young. I have to continue improving. I have four grand slams already, and I want to have more, if it's possible, on a different surface."

Asked for his best memory of playing on grass, the 22-year-old added: "I think I have at the same time the best, at the same time the worst: the final last year at Wimbledon.

"I played an unbelievable match, but at the same time I lost a good chance to win my favourite tournament."

Nadal could face Andy Roddick in the Queen's semi-finals and the defending champion earlier overcame a slow start to beat fellow American Robby Ginepri 6-7
(8/6) 6-1 6-1 on centre court.

Bidding for a record fifth title, Roddick lost the opening set on a tie-break but stormed back to win 12 of the last 14 games on his comeback from a shoulder injury which forced him to miss the French Open.

Roddick has twice reached the Wimbledon final - beaten by Federer on both occasions - and lost in the quarter-finals to Richard Gasquet last year after squandering a two-set lead.

"Going into Wimbledon with no preparation isn't ideal," said the 25-year-old former US Open champion.

"I think I really do need this week. I think we have it under control now. I've been hitting four, five days in a row and it's pulled up all right since I've been here.

"I've never had a problem with my shoulder before in eight years. It's probably been the best part of me physically. Especially with the way I play, I think if we were going to err, we were going to err on the side of being overly-cautious with it, which I think long-term was a smart way to go.

"My goal was just to be able to be ready to play here. We accomplished that. I feel healthy, the strength is coming back."

Fellow four-time champion Lleyton Hewitt also advanced to the third round with a 6-3 6-2 victory over Belgium's Xavier Malisse, while second seed Novak Djokovic defeated Croatia's Roko Karanusic 6-2 7-6 (9/7).

Djokovic, beaten by Nadal in the semi-finals in Paris, cruised through the opening set but needed to save two set points in the tie-break before sealing victory with a superb backhand drop shot.

"I always look forward to playing on grass because we don't get many chances and it's much slower this year which suits my game," said Djokovic, the Australian Open champion.

"I'm getting used to the grass and one day I would like to win Wimbledon, which is my favourite grand slam."