Aussies break 4x100m relay world record in never-before-seen moment

Australia's 4x100m women's relay team have broken their own world record at the Tokyo Olympics, winning the Aussies' first gold medal at the 2021 Games.

The Aussie quarter of Bronte Campbell, Meg Harris, Emma McKeon and Cate Campbell defended their title in extraordinary scenes on Sunday.

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The Aussies torched their rivals in a time of three minutes 29.69 seconds, becoming the first women's team in history to break the 3:30 barrier in the event.

"You never see that," Aussie great Leisel Jones said in commentary for Channel 7.

The time bettered Australia's previous world benchmark of 3:30.05, set at the 2018 Commonwealth Games.

McKeon put the Aussies in the hunt for the world record with an insane third leg, before Cate Campbell brought it home.

For 19-year-old Harris, it was her first medal at her first Olympic Games.

The comprehensive victory - almost three seconds ahead of silver medallists Canada - delivered Australia a third-consecutive Olympic title in the event.

Cate Campbell, who with basketballer Patty Mills carried Australia's flag at Friday night's opening ceremony in Tokyo, has featured in all three relay victories.

At the 2016 Rio Games, she teamed with her sister Bronte, McKeon and Brittany Elmslie to collect gold.

And four years prior in London, Australia's team of Cate Campbell, Elmslie, Alicia Coutts and Mel Schlanger also saluted.

"I could not be prouder of these girls," Cate Campbell said.

"It has been a tough ask for everyone to get here and to come away with the win and a world record. You honestly couldn't have asked for anything better."

In Sunday's final in Tokyo, the Australians were gifted early momentum by Bronte Campbell, who left her team lurking ominously in second spot after her leg.

Harris then took the lead on the second leg and the Australians were never challenged thereafter, with McKeon and finally Campbell increasing their advantage.

"Incredible. There is no feeling like it," Harris said. "Last night swimming with Maddie I walked out and it was insane.

"Then to get the opportunity to do it again in the final is even better."

Australia erupts over incredible world record

It was the third medal for Australia in the swimming event on Day 2 in Tokyo after Jack McLoughlin and Brendon Smith won silver and bronze respectively.

McLoughlin came second in the 400m final while Smith was third in the 400m individual medley.

Fans flocked to social media in awe.

with AAP

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