Australia broke the women's 4x200m freestyle world record at swimming's world championships on Thursday, coming home in 7min, 37.50sec.
The United States were second on 7:41.38, while China were third on 7:44.40.
The team of Ariarne Titmus, Mollie O'Callaghan, Shayna Jack and Briana Throssell beat the record of 7:39.29 that Australia set at last year's Commonwealth Games in Birmingham.
Titmus, who won the 400m freestyle individual title in a world record on the competition's opening night, said "pushing each other in training every day" was the key to their success.
"We train together every day, and to come here and break a world record together is really special for us," she said.
Australia's 4x100m freestyle relay team set a new world record earlier in the competition.
O'Callaghan also broke the world record in the individual 200m freestyle.
Australia's Kyle Chalmers and Kaylee McKeown won individual titles on Thursday.