Trinidad and Tobago's Nikoli Blackman broke the national 15-17 record on Wednesday en route to winning his 50m freestyle semifinal to qualify for the World Junior Swimming Championship final.
Blackman, 18, who won three gold medals last month at the Commonwealth Youth Games, touched the wall in a blistering 22.33 seconds at the Wingate Institute Olympic swimming pool in Netanya, Israel.
Coming in second was Canadian Paul Dardis (22.73) followed by Italy's Davide Passafaro (22.73).
Australian Flynn Southam stopped the clock in a personal best 22.29 seconds to win semifinal two, ahead of Italian Lorenzo Ballarati (22.38) and USA's Diggory Dillingham (22.53).
With the second fastest time going into Thursday's final, which splashes off at 12.07pm, Blackman will be eyeing a place on the podium and his first medal of the championships.