Aussies smash swimming world record in remarkable feat: 'Insane'

Australian quartet Madi Wilson, Mollie O'Callaghan, Jack Cartwright and Kyle Chalmers led Australia to a world record in the mixed 4x100m relay swimming championships.

Chalmers swam a brilliant second leg, which would have boosted his confidence after a well below average performance in the 100m butterfly which saw miss out on a spot in the semi-finals on Thursday.

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The time set by the Aussies shaved two-hundredths of a second off the record set by the United States at the last worlds in Gwangju, South Korea, in July 2019 as they blew away Canada (3:20.61) and the US (3:21.09).

Chalmers swam a brilliant second leg, which would have booted his confidence after a well below average performance in the 100m butterfly which saw miss out on a spot in the semi-finals on Thursday.

"It's insane," declared the Rio Olympics 100m freestyle champ Chalmers.

"You have the world champion (O'Callaghan, 52.03sec), a girl who would probably have won silver if she'd been in the race (Wilson, 52.25), Jack (Cartwright, 48.12) coming back from shoulder surgery to swim an amazing first split ... I think we were always going to be hard to beat."

Chalmers' own leg of 46.98 set the Aussies up for an unassailable lead early in the race.

"I'm extremely happy, so proud of this team, it's just an amazing result," said O'Callaghan, who now boasts five medals from the championships, including three golds.

Kaylee McKeown wins gold at World Championships

Earlier, Kaylee McKeown has underlined her standing as one of Australia's marquee swimmers with her first world championship triumph in the 200m backstroke in Budapest on a milestone penultimate day for the Dolphins.

Triple Olympic champion Kaylee McKeown, who had previously won five world silvers, including two already this week in Budapest, broke her golden duck with a nail-biting triumph in the 200m backstroke.

"To come away with a gold medal is pretty spectacular, I wasn't expecting to be here at the beginning of the year, so to come out with two individual podium swims is amazing," said McKeown, who also won silver in the 200m individual medley.

"I was really nervous coming in tonight off the back of last year but it's an awesome feeling."

It was also a night of high emotion for McKeown, who dedicated her medal to her late father.

"You'll quite often see me before my warm up, I'll sit on the edge of the pool and have a little a moment for myself. I believe in my little way that he is there every step of the way, so that's my thank you," she said.

with AAP

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