'Insane': Aussie stuns swimming world in never-before-seen moment

Aussie star Zac Stubblety-Cook has shocked the swimming world after becoming the first man in history to swim a sub-two minute, 0.6 second time in the 200m breaststroke.

Stubblety-Cook clocked two minutes, 05.95 seconds on Thursday night at the Australian trials in Adelaide, bettering the previous world record of 2:06.12 set by Russian Anton Chupkov in 2019.

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The 23-year-old, who won gold at the Tokyo Olympics in 2021, even surprised himself when he swam the fastest 200m breaststroke time ever.

"It's a lot to wrap your head around," Stubblety-Cook said of his world record.

"It's a bit surreal to be perfectly honest.

"I was obviously hoping to swim fast and hoping to swim close to my best.

"But that is just something else."

The Brisbane-born athlete who cites being curious, driven and stubborn as his top-three character traits had pondered breaking the world record in his pet event.

But it wasn't a burning motivation.

"I had thought about it ... but I never have been like 'yes, that's it, I want to break the world record'," Stubblety-Cook said.

"It happened obviously ... but I didn't think we were going that fast."

However the 23-year-old says there's room for improvement on his record-breaking victory.

"I am not sure," Stubblety-Cook said when asked how much faster he can go.

"I am probably much more process driven than outcome driven.

"But I think I can continue to build that front-end a bit more.

"And we have spoken about it, doing a bit more 100 (metre) work and building through that (first) 100 a little bit quicker."

Stubblety-Cook said he was banking on being driven faster by stiffer competition at next month's world titles in Budapest.

"When I race in a world-class event at a world champs it will be even better," he said after beating Matt Wilson by 4.19 seconds in Adelaide.

Kyle Chalmers backflip to ruin Cody Simpson dream?

Stubblety-Cook's world record came on a night when Kyle Chalmers signalled a backflip which will deny pop star Cody Simpson an international swimming debut at the looming world titles.

Chalmers had previously announced that he won't swim at next month's worlds in Budapest.

But after winning the 50m butterfly and finishing second in the 100m in Adelaide, Chalmers is set to reverse that decision.

His likely change of mind will prevent Simpson making his Australian debut at the world titles.

The top two in each final at the nationals earn selection for the worlds, with the top three securing a Commonwealth Games berth.

Chalmers finished second behind Matt Temple in Wednesday night's 100m butterfly final, with Simpson third.

With no Chalmers, selectors were expected to pick Simpson for the 100m fly at the worlds. But with Chalmers, Simpson will be squeezed out.

"You can't make me out to be the villain," Chalmers said after his 50m victory on Thursday night.

"For me, it's unfortunate it probably takes Cody's spot away."

Simpson remains assured of selection for the Commonwealth Games in July-August.

Other Thursday night winners included Kaylee McKeown (women's 4x100m medley), Brianna Throssell (women's 100m butterfly), Chelsea Hodges (women's 50m breaststroke) and Zac Incerti (men's 200m freestyle).

with AAP

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