Petr Korda, the reigning Australian Open champion who tested positive for the banned anabolic steroid, nandrolone, during Wimbledon last year, duly won his opening match in Melbourne yesterday, but the anger engendered by the decision not to ban him continued to fuel heated discussion and spawn inflammatory statements from his fellow players.

America's Jim Courier, who won four Grand Slam tournaments between 1991 and 1993, claimed only drug cheats could survive the gruelling season. He said he suspected widespread blood doping in the sport, including the use of erythropoietin, or EPO, which artificially increases red corpuscles in the blood, thereby increasing stamina and recovery rates. "I have no proof and I can't name names but I will be pretty pissed off in 10 years if I find out people were doing that and I had been losing to them," Courier said.

"When almost half the Tour de France were booted out for doing that type of nonsense last year, it's clearly prevalent in Europe and European sports. And most of our Tour is in Europe, so by deduction I'm throwing darts.

"I can't play 35 weeks a year and keep going, and I don't think anybody else can either. But they are."

His claims were immediately and angrily countered by Austria's Thomas Muster, the 1995 French Open champion, who said Courier was "on the edge of destroying the sport.

"I am 32 years old. I am not taking drugs, and I am still playing maybe 30 weeks a year. If you don't have proof, you shouldn't say things like this," added Muster, who then attacked Mark Miles, the chief executive officer of the ATP Tour, the men's ruling body, for being ineffectual and failing to give the players adequate support and protection in matters of drug abuse.

Korda, having tested positive, escaped a one-year ban when the ITF's independent appeals committee accepted there were "exceptional circumstances", with the Czech claiming he and his advisers had made "exhaustive efforts to find the source of the substance, but without success". Korda was docked his Wimbledon prize money and his ranking points.

This incensed the players, forcing the ITF to lodge an appeal with the Court of Arbitration for Sport in Switzerland in a belated effort to secure a 12-month ban. Korda then lodged a counter-appeal in the High Court and there, for the time being, the matter rests legally, although the ITF remains confident that the issue of "exceptional circumstances" has been misinterpreted.

Before last March a ban for steroid abuse would have been automatic, but then the ITF, in conjunction with the ATP Tour, added a paragraph intended to ameliorate such a ban if the player "did not know that he had taken, or been administered, the relevant substance provided that he had acted reasonably in all the relevant circumstances".