Spaniard Tommy Robredo accused Novak Djokovic [Images] of exaggerating the seriousness of his injuries to get some extra rest during their draining five-set tussle in the fourth round of the US Open [Images] on Tuesday.

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Djokovic took an injury time midway through the second set to get a painful hip treated, complained of an upset stomach and also appeared to be hobbling around court after rolling his ankle.

Robredo, who lost 4-6, 6-2, 6-3, 5-7, 6-3, did not seem too sympathetic.

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"I have pain, as well. I was running like hell and my feet were burning but I say nothing," said Robredo, who tumbled to the ground in the fifth set while lunging after a Djokovic shot.

"I think that if you're not fit enough, then don't play.

"But after every time he was asking for a trainer, he was running like hell and he was making the shot. But he does what he does a lot of times."

Robredo felt Djokovic was taking advantage of rules that allowed players to receive multiple medical breaks provided it was a new problem that needed to be treated by the trainer.

It is not the first time that Djokovic has been accused of stretching the rules.

In 2006 and 2007, he was criticised by many opponents, including Roger Federer [Images] during a Davis Cup rubber, for seeking medical times outs at critical junctures in a match.

"So I think we should take care a lot more of these things, because one thing is that if you fell down like I did, I can have blood and it's normal that trainer gets in because there's blood or whatever," said Robredo.

"But for having pain, I had pain, as well, all over my body because I think I run a lot more than him and I said nothing.

"So did I trust (believe) him? No. I think he took his time because he did it because he was a little bit more tired and that's a part of the game. It helped him a lot."

Djokovic's next opponent, Andy Roddick [Images], was already making a mental note of the medical time outs the Serbian can request when they meet in the quarter-finals on Thursday.

"A back and a hip? And a cramp?... bird flu... anthrax... SARS... common cough and cold," Roddick listed for reporters.

"If its there, it's there, there's just a lot. He's either quick to call a trainer or he's the most courageous guy of all time. It's up to you guys to decide."

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