Shanghai - ATP executive candidate Brad Drewitt on Thursday defended the decision to increase the 2009 player workload in exchange for more prize money after Andy Roddick charged that an over-heated schedule is leading to injuries on court.

Roddick withdrew with some frustration on Wednesday after rolling his ankle in training and handing a spot in the eight-man Masters Cup wrap-up event to alternate Radek Stepanek.

The crowded calendar situation is expected to improve only slightly in 2009 without the distraction of an Olympics. But under new rules, leading players will be required to play all eight of the newly branded Masters 1000 events.

Australian Drewett is on a short list of candidates to replace outgoing ATP supremo Etienne de Villiers from early 2009.

"It was not just one or two people (who made the new schedule)," said the Australian tournament director of Shanghai. "I have spoken to Andy about this. I respect his opinion."

Roddick said that the calendar is leading to injuries, most specifically the knee tendinitis which kept number one Rafael Nadal from both Shanghai and next weekend's Davis Cup final.

"This particular injury had nothing to do with it being a long season," said Roddick after his withdrawal. "I've been pretty forthright in my opinions on regarding the schedule and it being too long.

"I think too much is asked of us as far as playing 11 months of the year, and now they're imposing more mandatory tournaments. It doesn't make a whole a lot of sense. It's unfortunate for someone like Rafa that goes out there and does things the right way.

"No one is ever going to question how much effort he gives every time he's on the court. I don't think anybody wants to be on the court more than he does, at a certain point you would hope they start respecting our opinions a little bit more."

Shanghai will become one of the elite series in 2009 after hosting the year-end championships for the past four years.

In addition, Hamburg, which was demoted from a Masters to a regular event by the ATP and went through a losing summer lawsuit before the change could be implemented, announced that it will stage its new event as planned on clay next July.

The Germans are still appealing against a US court ruling which gave the ATP the right to determine the men's tennis schedule. (dpa)