Michael Phelps: I don't know if the sport has ever been clean

American Olympic champion swimmer Michael Phelps reveals frustration over recent doping scandal and says it's upsetting that WADA cannot control it

Rio de Janeiro: As the Russian doping scandal roils Rio, Olympic swimming star Michael Phelps says he can't be sure he has ever competed in a completely clean sport.

US swimmer Michael Phelps will be participating in his fifth Olympics at Rio. Pic/Getty Images

"We all want clean sports. That's all we want," the 18-time gold medallist said in Rio, where he's preparing for a fifth Olympic campaign.

"I think I can honestly say as well in my career I don't know if I've ever competed in a clean sport. It's very upsetting." More than 100 Russians, including seven swimmers, have been banned from Rio after revelations of a state-run scheme to cover up positive drug test results.

The International Olympic Committee declined to ban Russia outright, tasking sports federations with determining which Russians can compete. Phelps said that when he steps on the blocks at the Rio Olympic Aquatics Stadium he won't worry about whether his rivals are clean.

Michael Phelps

"There's not really a lot that I can control but me," he said. "That's the main priority for me."

But the 31-year-old admits he's dismayed at the lack of progress. "It's something that needs to change about all sport, not just swimming," he said.

"We've had this problem for how many Olympics now — it seems almost every time there's something that comes up.

"It's sad. It's really sad that we can't control it. That somebody who is in charge cannot control this."

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