LONDON(AP) Andy Roddick opened his grass-court season Tuesday by beating Kristof Vliegen of Belgium 6-1, 6-4 in the second round of the Queen's Club tournament.

The No. 2-seeded American, a four-time winner at the Wimbledon warmup event, broke twice to win the first set in 18 minutes.

Vliegen played better after he had his right ankle taped, but Roddick broke again to lead 5-4 and served out the match with his 11th ace.

Coming from the clay to the grass is one of the happiest days of my year,'' Roddick said.There's not a lot of adjustments to be made to my game to suit the grass. I feel I can take it for what it is and just get out there and play.

``I thought I served well today. I thought I returned well at times. It was pretty solid all around. I just kind of wanted to get it in before there was a chance for it to rain on us. I was happy with it.''

Former No. 1 Juan Carlos Ferrero captured his 400th career singles victory when Sebastien Grosjean of France retired with a right shoulder injury while trailing 6-2, 2-1.

The 31-year-old Grosjean, who finished as runner-up to Roddick in 2003 and '04, was playing his first ATP match since October. He had shoulder surgery in November.

Alberto Martin of Spain upset 13th-seeded Ernests Gulbis of Latvia 7-6 (9), 6-4, and Steve Darcis of Belgium rallied to beat Chile's Paul Capdeville 3-6, 6-3, 6-4.