South Africa have requested that all 44 players involved in Saturday's Test here against Australia be tested for illegal drugs in the light of accusations that the Australian Rugby Union has been involved in a cover-up.

Rudolf Straeuli, the Springboks coach, made the call after it was disclosed that the union had ignored a failed dope test unofficially given to the Wallaby wing Ben Tune in March 2001, when he was playing for the Queensland Reds.

The ARU said it had been informed at the time by the Queensland Rugby Union and admitted that the player had been stood down for four Super 12 matches until traces of a substance, probenecid, often administered with antibiotics in treating infections but also used as a masking agent for steroids, had cleared his system.

The ARU claims the drug was innocently prescribed to speed his recovery from a knee infection. Once it was realised what Tune had been given, he was privately tested and only returned after his system had cleared.

"It's disturbing to see that something like this could be concealed," Straeuli said. "It would be in the interests of the game if the IRB or alternatively Sanzar [the southern hemisphere umbrella body involving the South African, New Zealand and Australian unions] that both teams be drug tested before Saturday's game."

A spokesman for the Walla bies described the suggestion as "pointless", but the International Rugby Board has requested a chronology of events from the ARU and stated that its regulations "include notice and disclosure obligations on unions".

In the event of a failed test the IRB requires players to be called before an independent tribunal. If the presence of a banned substance is proved the mandatory sentence is a two-year suspension.

John O'Neill, the managing director of the ARU, said it had acted "with good intentions". He added: "It's a difficult decision, particularly when the player is the unintended victim of an oversight. His reputation did not deserve to be tarnished. We are required to notify the International Rugby Board and that did not happen. We need to address that."

In reply to all this, Tune, who was at the Wallabies' secluded training camp in Coffs Harbour, insisted he had done nothing wrong and that it was a private medical matter. The public, he said, "had no real right to be concerned with that stuff. I got a pretty serious infection in the knee which needed treating and unfortunately I was given a substance that was banned by the IRB. I sat out a couple of games and did the right thing under medical advice and advice from the Queensland union."

That union's chief executive, Jeff Miller, said: "There was no cover-up ... there was no obligation to tell the IRB because the ARU is responsible for administering the anti-doping policy for domestic matches."