LONDON(AP) French Open champion Rafael Nadal made a smooth adjustment from clay to grass Wednesday, defeating Marcos Daniel in straight sets to reach the third round of the Queen's Club tournament.

The top-seeded Nadal, who captured his fifth Roland Garros title on Sunday, began his Wimbledon preparations with a 6-2, 6-2 victory under rainy London skies.

The Spaniard, who had a bye in the first round, was joined in the last 16 by second-seeded Novak Djokovic, who beat Italy's Paolo Lorenzi 6-3, 6-3, and Sam Querrey, who knocked out fellow American Robby Ginepri 7-6 (4), 6-2.

It was Nadal's first match on grass since his epic five-set win over Roger Federer in the 2008 Wimbledon final. Nadal missed the grass-court season last year with knee problems.

Nadal, who beat Robin Soderling in the French Open final Sunday to supplant Federer at No. 1 in the rankings, looked comfortable on the grass against his 112th-ranked Brazilian opponent.

``It's difficult to adapt but I am happy to be back on grass, it is one of the surfaces I enjoy playing on,'' said Nadal, who faces Uzbekistan's Denis Istomin in the third round.

Play was stopped by light rain with Nadal leading 2-1 in the second set, and he signed autographs as he left the court. When play resumed after a 14-minute delay, Nadal broke at love to lead 4-2 when Daniel made a forehand error.

Nadal said he needs a few more matches to feel comfortable on grass.

After having the good results on grass ... I start to believe I can play well on this surface,'' Nadal said.So that makes me feel a little bit better mentally when I come back here. But at the same time, I need the time because I have to adapt, and that needs more days.''