Australia kicked off the swimming competition at the World Aquatics Championships – Singapore 2025 in record-breaking form, powering to victory in both men’s and women’s 4x100m freestyle relays on Sunday night at the OCBC Aquatic Centre.

The men’s quartet of Flynn Southam, Kai Taylor, Maximillian Giuliani and Kyle Chalmers stormed to gold in 3:08.97 – a new Championship Record – beating Italy (3:09.58) and the United States (3:09.64) in a fiercely contested final. “That’s crazy,” said Chalmers, the anchor. “We believed we could do it and we did it. It’s something we’ve been building for a few years now… just about believing in each other and doing it when it counts.”

For Chalmers, the gold held deep personal meaning. “I debuted on this relay 10 years ago and we missed the final… then we got a bronze, then silver, then gold in 2023 – and now the championship record,” he said. “I’m super excited about the future and just honoured to be a part of this team.” He also shared a touching moment post-race: “My grandparents and mum were in the stands tonight… that was the first thing I thought of when I touched the wall.”

The Aussie women added to the celebration with a 3:30.60 win in their 4x100m freestyle relay, holding off a stacked Team USA anchored by Gretchen Walsh and Torri Huske (3:31.04). The Netherlands took bronze with a 3:33.89 finish.

There was more star power on display in the 400m freestyle events as Germany’s Lukas Martens and Canada’s Summer McIntosh both delivered wins. Martens topped Australian Samuel Short and Korea’s Kim Woomin, while McIntosh outpaced Chinese silver medallist Li Bingjie and American icon Katie Ledecky, who settled for bronze.

Singapore had standout moments of their own, headlined by Olympian Gan Ching Hwee breaking a 16-year national record in the women’s 400m freestyle with a time of 4:09.81. Letitia Sim (27th in 200m IM), Quah Jing Wen (T-24th in 100m butterfly), and Jonathan Tan – who anchored the men’s 4x100m relay with Ardi Azman, Mikkel Lee, and Glen Lim (18th in 3:18.38) – all made their Singapore 2025 debuts. Glen Lim also swam the 400m freestyle earlier in 3:54.97, while Teong Tzen Wei clocked 23.38s in the men’s 50m butterfly to place 22nd overall.