World silver for super Sam

Sam Short, the former Albany Creek swimmer, won his second medal of the World Championships last night - in an Australian record time.

The 19-year-old took silver in the 800m freestyle final clocking 7 minutes 37.76 seconds to beat his hero Grant Hackett’s previous record of 7:38.65.

"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."

Short appeared on course for gold, but Olympic 400m champion Ahmed Hafnaoui took the title in 7:37.00, to reverse the places in the 400m two days ago.

That race saw Short, who went to Prince of Peace Lutheran College in Everton Hills, take the title by just 0.02 of a second in Japan.

Kaylee McKeown, who spent her junior career at Australian Crawl in Burpengary, collected a silver medal as part of Australia’s 4x100m mixed medley relay team.

McKeown, Zac Stubblety-Cook, Matt Temple and Shayna Jack were 2.08 seconds behind entering the last freestyle leg.

Jack closed the gap but the Australian quartet finished 0.46 seconds shy of the Chinese.

McKeown was second-fastest into the women's 50m backstroke final, logging a time of 27.26 in her semi-final.

However, the headlines belong to Molly O'Callaghan, from Logan, who broke the oldest world record in women's swimming - and then broke down.

The 19-year-old is a swirl of emotion after achieving what she thought was impossible. "I was a wreck," O'Callaghan said.

"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."

O'Callaghan clocked one minute 52.85 seconds, eclipsing the 1:52.98 set by Italian Federica Pellegrini in the supersuit era in 2009.

Australia is currently on top of the medal table at the halfway mark of the championships with six gold and three silver; ahead of China (4-0-4) and USA (3-7-7).