Mollie O'Callaghan pips Ariarne Titmus to break oldest world record in swimming

Mollie O'Callaghan is the toast of the swimming world after breaking the longest-standing women's world record in Fukuoka on Wednesday night. The Aussie star pipped her more fancied compatriot Ariarne Titmus to win gold in the 200m freestyle at the world championships, breaking the world record set by Federica Pellegrini in the super-suit era in 2009.

The 19-year-old clocked one minute 52.85 seconds, eclipsing the previous mark of 1:52.98 - which stood for 14 years and was the longest-standing world record in women's swimming. It also marks the first time an Australian has held the record since Shane Gould 55 years ago.

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"I was a wreck," O'Callaghan said after creating history. "I kind of looked (at the results board) and I was a bit like 'oh, is that me or not?'. I couldn't really explain it in the moment.

"There was tears. There was happiness. Very mixed emotions. I am just so proud of myself to do that. It was such an unexpected moment."

Titmus had to settle for the silver medal as O'Callaghan shocked the swimming world. O'Callagan overtook teammate Titmus (1:53.01) in the last 20 metres, and the pair have now both set world records in Fukuoka following Titmus' 400m freestyle triumph on Sunday night.

“A moment we will never forget. Mollie O’Callaghan is the world record holder," commentator Mat Thompson said. "The last Australian to hold it before tonight was Shane Gould in 1972."

Giaan Rooney said: “It has been said before but it is relevant now, good golly, Miss Mollie. This is extraordinary. I was talking about Arnie (Titmus) being under PB pace. Mollie’s PB of 1:53.03, she has blown it out of the water. She has taken a second off that.

"The timing is exceptional. Knowing she withdrew from one of the events as well. She had a knee problem. Such an impressive swimmer. It is not just in this race.”

It was a remarkable achievement for the Queenslander who dislocated her kneecap at training six weeks ago. "Obviously there's doubts coming with that (injury) ... I had a modified program leading in to this," O'Callaghan said.

Sam Short breaks Grant Hackett's Australian record

Also on Wednesday night, fellow teenager Sam Short (800m freestyle) and the Aussie 4x100m mixed medley team won silver medals. Short, who won gold in the 400m freestyle on the opening night, touched the wall in 7:37.76 to better Grant Hackett's Australian record of 7:38.65, set in 2005.

"Grant is one of my heroes, I have looked up to him my whole life," Short said. "And even though I came second, I am over the moon with the time."

Australia's 4x100m mixed medley team of Kaylee McKeown, Zac Stubblety-Cook, Matt Temple and Shayna Jack took silver behind China. After being 2.08 seconds behind entering the last freestyle leg, Jack managed to close the gap, but the Australians finished 0.46 seconds shy of the Chinese.

And Kyle Chalmers issued an ominous warning in the 100m freestyle semi-finals, qualifying second-fastest. The 25-year-old posted a time of 47.52 and will be the oldest swimmer in the gold medal race.

"I have definitely got a bit of confidence ... I have been through it quite a few times," he said.

with AAP

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