Australian swimming megastars Mollie O'Callaghan and Kaylee McKeown both shattered short course world records during the second leg of the World Cup in Westmont, Illinois, kicking off the nation's post-Ariarne Titmus era in style.
O'Callaghan, the reigning 200m Olympic champion, posted a blistering 1:49.77 in the event to beat compatriot Lani Pallister to gold. The 21-year-old from St Peter's Western broke Siobhán Haughey's mark of 1:50.31, set at the short course world championships in 2021, with a dominant swim from start to finish.
Twenty-four hours later, McKeown prevailed over long-time rival Regan Smith in the 200m backstroke final. Both swimmers touched the wall in times that were quicker than the previous world record, held by Smith, but it was McKeown who took the gold medal, stopping the clock in 1:57.87.
O'Callaghan and McKeown's world record swims earned them bonus cheques of US$10,000 (AU$15,300).
Earlier in the meet, Smith prevailed over McKeown in the 100m distance, breaking her own world record with a swim of 54.02s. Meanwhile, O'Callaghan completed the medal set in Westmont, claiming bronze in the 50m freestyle and silver in the 100m freestyle, behind American Kate Douglass.
Last week, Titmus, Australia's four-time Olympic champion, stunned the swimming world by announcing her retirement from the sport at age 25.
Titmus, who famously rose to global prominence at the Tokyo Games in 2021 where she triumphed over Katie Ledecky in an epic women's 400-meter race, had taken the full season off following last year's Olympics in Paris and was expected to make her return to the pool in the coming months. However, on Thursday morning, she took to Instagram to confirm she would no longer be representing Australia in the pool.
"I've made the decision to retire from competitive swimming," Titmus said. "A tough one. A really tough one, but one that I'm really happy with. I love swimming, but I guess I've taken this time away from the sport and realised some things in my life are just a bit more important to me now than swimming."