Guernsey's Miles Munro set a new island record but went out in his semi-final of the 50m butterfly at the 2014 Commonwealth Games in Glasgow.
The 18-year-old finished seventh in a time of 24.49 to take 0.67 off his previous personal best from his heat.
Fellow islanders Tom Hollingsworth (26.22) and Alexander Beaton (26.53) failed to progress out of the heats.
In the 100m backstroke, James Jurkiewicz won his heat in 1:10.29, but did not make the semi-finals.
"I'm really happy and the time was a massive personal best," Munro told BBC Radio Guernsey.
"I've knocked 1.3 seconds off what I'd swam coming into this competition," he added.