37.

50 at the 2023 World Championships: O'Callaghan, Jack, Titmus, and Brianna Throssell were in action—and all made the final.

Lani Pallister, who swam in the heats ahead of that world record swim also booked her place in the final, although fellow heats swimmer Kiah Melverton was only fast enough for 12th.

**'I have been a heats swimmer two World Champs in a row, and it sucks,'** Pallister, who qualified third-fastest, said after her heat swim on Wednesday morning.

**'I understand the importance in playing a part and that sort of thing but I think there's a huge difference in having the opportunity to stand up in a final.

It's one of Australia's most important events and I think it's an event that we have the opportunity to do really well in.

'**Nervous energy crackles through the Brisbane Aquatic Centre ahead of the Australian Olympic trials, and nobody is immune from its effect.

Also in the field were a further three women who won bronze in the 2020 Olympics in Leah Neale, Meg Harris, and Tamsin Cook, with Harris qualifying seventh-fastest for Wednesday night's final.

Only Maddie Wilson is missing of the world record-breaking Fukuoka team, after announcing her pregnancy at Christmas with fiancé, Australian cricketer Matt Short.

O'Callaghan, who qualified for the Olympic team in the 100m backstroke on Tuesday, said she was **'very, very nervous'** about the 200m free when she spoke to the media.

**'There's a lot of pressure riding on this event, especially having the world record in it,'** she said.

**'Whatever happens, happens, I would really love to make the team on this event and do the best job that I can.

'**She appeared confident in leading out the first heat of the day, reeling in fast-starter 18-year-old Hannah Casey to qualify second fastest behind 400m world record holder Titmus, who comfortably won the second heat.

Jamie Perkins (fourth-fastest) and Brittany Castelluzzo (eighth-fastest) completed the qualifiers for tonight's final, which Jack said will be must-watch.

We acknowledge Aboriginal and Torres Strait Islander peoples as the First Australians and Traditional Custodians of the lands where we live, learn, and work.

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