AMERICAN Andy Roddick stayed on course for a fifth AEGON Championships title as he eased past Kristof Vliegen - then admitted he's relieved to be back on his favourite service.

The big-serving number two seed beat the Belgian in straight sets to set up a third-round clash with either Lleyton Hewitt or Frederico Gil.

And the 26-year-old says he's delighted the clay-court season is over so he can get back to business on grass.

He said: "Coming from clay to grass is one of the happiest days of my career because there's not a lot of adjustments to be made to my game to suit grass.

"I feel like I can just get out there and play. On clay I need to make a lot more adjustments. It's a welcome change."

Fellow countrymen James Blake and Mardy Fish joined Roddick in the next round with victories over Ivan Ljubicic and Michael Llodra respectively. 

But former finalist Sebastien Grosjean made an early exit after he retired against Juan Carlos Ferrero.