'Nothing worse': Aussie legend reveals truth of Mack Horton controversy

While Mack Horton hasn’t formally explained his stunning podium protest of Sun Yang, Aussie legend Susie O’Neill has attempted to explain what was going through his head.

Horton created an international furore when he did not shake hands with Sun and refused to join him on the podium after being relegated to 400m silver by the 10-time world champion on Sunday night.

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The protest warranted world body FINA to issue an official warning to Horton and Swimming Australia late on Monday night.

However fellow swimmers reportedly gave Horton a standing ovation as he returned to the athletes’ village, and he has the full support of O’Neill as well.

“I really respect Mack for what he did,” O’Neill said on The Project.

“It’s tough, you know? But as athletes, we really want to compete in a fair playground. And if you feel like it’s not being policed well enough, then it just gets really, really frustrating for the athletes.

“So, I really commend him for coming out. I’m really passionate about clean sport. I competed in the ‘90s against some people who weren’t clean.

“When I was an athlete, I wasn’t allowed to speak out. We had to keep our mouths shut. I’m really, really passionate about clean sport, about policing the sport to make it clean. I’m all for Mack standing up for that.”

O’Neill said it’s incredibly frustrating for athletes when they’re narrowly beaten by rivals suspected of cheating.

“There’s nothing worse than dedicating your whole life to an event and it being taken away from you by a drug cheat,” she said.

“As athletes, you put 40 hours a week into your training. You’re training for years and years.

“Then you get to an event, where you’ve got a one-in-four years’ chance to compete, and you don’t feel like it’s a fair atmosphere or field, it is very, very frustrating.

“I think we should commend Mack for putting a spotlight on the sport. I’m not saying anyone is definitely taking drugs, let’s police the sport and have the same rules for everyone.”

Horton and Sun to clash again

The bitter stoush between Horton and Sun isn't going away any time soon either, with the rivals to feature in Tuesday's 800m freestyle.

The fallout over Olympic champion Horton's 400m freestyle podium protest against Sun at Gwangju appears to have no end, with the Australian even receiving death threats on social media over his stance.

Yet it may only escalate when Horton and triple Olympic champion Sun contest the 800m freestyle heats on Tuesday.

Horton is not happy that Sun, who served a 2014 doping ban, has been allowed to compete ahead of a Court of Arbitration for Sport hearing in September that may end the Chinese star's career.

Sun has been accused of smashing vials of his blood with a hammer during a clash last year with testers.

He faces a lifetime ban if found guilty.

with AAP