Uttoxeter's Adam Peaty broke the 50m breaststroke world record in the semi-finals at the European Championships yesterday.
The 19-year-old, who has already won two golds in Berlin, won his semi-final in a time of 26.62 seconds.
The old record of 26.67 seconds was set by Cameron van der Burgh of South Africa in July 2009, when swimmers were using performance-enhancing body suits.
"I feel absolutely amazing. I looked at the scoreboard about five times before I knew I had broken it," he said.
"I haven't broken a world record before so I don't know how it feels.
Peaty is competing at only his second major international event, having made his debut at last month's Commonwealth Games in Glasgow, where he won two golds and a silver for England.