Adam Peaty has broken his own world record in the men's 100 metre breaststroke at the World Championships in Gwangju, South Korea.
Peaty, 24, smashed the previous record of 57.10 seconds he set at last year's European Championships to win in 56.88.
In doing so, the Britain achieved one of his career goals of becoming the first man to break the 57-second barrier in the event.
Peaty finished close to two seconds ahead of China's Yan Zibei, who finished the first semi-final in second place in 58.67, with fellow Briton James Wilby third in 58.83.
Uttoxeter-born Peaty swam the first 50 metres in 26.63 and the second in 30.25, both quicker than his previous world record splits of 26.75 and 30.35.
He has now swum the event 1.4 seconds faster than anyone else in history and has set the best 16 times ever recorded in the 100m breaststroke.
Peaty said: "It feels incredible! I've been chasing that for three years now ever since I touched the wall in Rio I knew I could go faster.
"I said this morning I wasn't going to chase 56, I was going to let it come to me, and that's exactly what we've done."
Additional reporting by the Press Association.