American Andy Roddick suggested the stickiness of the surface could be partly to blame for a host of injuries and upsets.

Roddick twisted his ankle while trying to turn during his second round match against Ivan Ljubicic.

"Rebound Ace is pretty renowned for being a pretty sticky surface," Roddick said after the incident.

"A lot of injuries and cramping and stuff I think have been going down this week, so maybe that has something to do with it."

Mark Philippoussis also said that a quadriceps muscle injury he suffered earlier in the week had been caused by the stickiness of the courts.

"The surface is very tough on your body. Rebound Ace, it's very sticky," he said.

"Your shoes actually stick into the court that little bit longer and you feel that in your joints, your lower back and legs."

However, McNamee said that the court surface was not to blame for the high injury count at the tournament.

"We've only had one ankle (injury) at this tournament," he said.

"From 128 men, 128 women, you're going to get injuries, unfortunately. And that happens at every hardcourt tournament.

"It is going to happen early in the year, there's no doubt about that when they're coming off a break, that is a little bit of a factor," he told Melbourne daily The Age.

Competitive

Ljubicic, who advanced to the third round courtesy of Roddick's injury, blamed the crop of injuries on a combination of the timing of the event and an increasing number of matches that require a deciding set.

"Look at how many players are calling trainers onto the court these days," he said.

"I think we are all fit, but when you are not competing for two months and then come back it is a different type of stress you are finding on a court."