Australian Olympic swimming champion Zac Stubblety-Cook has refused to rule out staging a stadium protest over perceived failures in anti-doping testing.

Stubblety-Cook beat Arno Kamminga of the Netherlands to win gold for Australia in the 200-metre breaststroke at the Tokyo Games.

In Paris, he will defend his title against China’s Qin Haiyang. 

Qin, who broke Stubblety-Cook’s world record in the event last year, was revealed to be one of 23 Chinese swimmers who tested positive to the banned substance, trimetazidine, ahead of the Tokyo Olympics, but were still allowed to compete.

The swimmers avoided sanction after Chinese sports authorities and the World Anti-Doping Agency (Wada) accepted the positive tests arose from environmental contamination.

Three swimmers who tested positive won gold for China in Tokyo.

On Friday morning (AEST), Stubblety-Cook said he would “decide on the day” whether he would protest the WADA decision on the Olympic podium.

Qin was one of 23 athletes allowed to compete in Tokyo despite positive tests. Photo: Getty

Podium protests are banned under the International Olympic Committee’s rule 50, with athletes to do so facing a variety of punishments.

‘Everyone probably is aware of rule 50 here and the repercussions that happen with that,’ Stubblety-Cook said, adding “I think potentially we could see protests in other events as well”.

‘Personally, I think I will make a decision probably on the day,” he said.

Stubblety-Cook also said he felt the anti-doping system had “failed” clean athletes.

“At the end of the day, I’m a clean athlete and I’m trying to abide by those rules and I just hope my competitors do the same,” he said.

‘I absolutely believe in clean sport and I hope that this is clean games,’ he said.

Stubblety-Cook said it was disappointing to hear that 23 athletes tested positive, “some multiple times”, ahead of Tokyo.

‘I think it’s less about what country they came from and more about the system and how the system ultimately, it feels like it’s failed,” he said.