Retiring rugby league star Shane Webcke has revealed he tested positive for a banned drug but escaped punishment.

Webcke's admission is contained in his new biography Warhorse: Life, Football and Other Battles which is due to be released on Wednesday.

In an extract revealed by the Daily Telegraph, Webcke confirms how he tested positive to the banned substance probenecid after the Brisbane Broncos' opening match of the 2001 season against North Queensland.

Webcke, who is one of the game's most respected figures and a anti-drug campaigner, escaped suspension after it was accepted he had been prescribed the drug to recover from a serious knee infection.

"The news she (representative of the old Australian Sports Drug Agency) conveyed was the most shattering thing I had heard in my years in senior football," the Telegraph reported.

"I could see this blowing up to become a huge public controversy, with me pinned like a rabbit in the headlights ... and with the mud sticking.

Webcke said the matter had been dealt with in-house by ASDA and the NRL with the doctor's failure to register the probenecid prescription as an innocent mistake.

Webcke retired from rugby league a winner after the Broncos beat the Storm 15-8 in the 2006 grand final on Sunday at Telstra Stadium.

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