New father Cam McEvoy powered to the 50m freestyle world gold on Saturday in Singapore to go with his Olympic crown.
The 31-year-old Australian – who is at his seventh world championships – reclaimed the title he won in 2023.
McEvoy turned on the afterburners in the second half of the sprint to win in 21.14sec.
Britain's Ben Proud took silver in 21.26, with Jack Alexy of the United States in bronze in 21.46.
McEvoy's son Hartley was born only last month and the swimming ace gave a shoutout to his family after victory.
Being a father had given him a new outlook, he said.
"Unreal, it's been a pretty hectic preparation," said McEvoy.
"Just glad I got my hand on the wall first and in a great time.
"Enjoy it while it lasts, but I'm so excited to go home."