Former world No.4 Juan Martin del Potro admits he’ll have to fight through the pain barrier to defend his Sydney International title as he aims to put 11-months of injury hell behind him.

The 26-year-old’s world ranking has plummeted to 135 after he underwent wrist surgery in March.

He hasn’t played since retiring hurt in Dubai in February, but has been handed a Sydney wildcard and will take on Serbian world No.57 Sergiy Stakhovsky on Monday.

“I am so happy to be here once again and very grateful to get the wildcard,” the Argentine said.

“The wrist is OK but it will be a big challenge. But the doctors say it won’t get any worse playing at the highest level.”

The 2009 US Open champion won the Sydney event last year while nursing a problem with his left wrist but was dumped out in the second round at the Australian Open by Spain’s Roberto Bautista Agut.

His recovery from surgery has been slow and he admits the wrist problem – which also forced him to miss a chunk of the 2010 season – still pains him.

Yet he remains confident he can manage the problem and get his career back on track.

“The pain sometimes is high but sometimes it’s low,” he said.

“But I think after I play one match we’ll see how the wrist is and then look ahead.

“I have been easily beaten by some players in practise, but I need that.

“It feels much better than it did three weeks ago.”

Del Potro revealed he’ll need an extensive warm-up just to get him on the court to face Stakhovsky but said the lure of next week’s Australian Open in Melbourne is acting as a motivating factor.

“I do a long warm up, and that takes up a lot of time, but that is my life at the moment,” he said.

“The wrist bothers me still sometimes when I hit backhands. But I am trying to hit them harder because that is what I need to do.

“My goal is to finish well here, stay healthy, then go to Melbourne. This is a great opportunity for me.”