Malaysian swimmer Welson Sim smashed his own national record to win the men's 400m freestyle at the Mare Nostrum tour in Monaco on Saturday.
The 20-year-old, who represented the country at the Olympics last year, won in 3:49.48s ahead of 2016 Olympics gold medalist Mack Horton and China's Qiu Ziao.
His previous personal best was 3:50.33, which was recorded at the Singapore National Age Group Championships in March 2016.
In doing so, he became the second Malaysian to win gold at the Mare Nostrum tour.
Malaysia's first-ever gold was won by Phee Jinq En in the women's 50m breastroke event last year.