Adam Peaty led home a British one-two to clinch his third straight world 100 metres breaststroke world title in South Korea, then admitted he was disappointed not to have lowered his own world record.
The 24-year-old clocked a winning time of 57.14 seconds in Gwangju, well ahead of team-mate and training partner James Wilby who eclipsed China's Yan Zibei to take an impressive silver.
It meant there was no repeat of Peaty's history-shattering performance in the semi-finals when he timed 56.88secs to become the first swimmer in his event to break the 57-second barrier.
But Peaty said his final time would serve as a reminder that he still has more to learn in his sport – and it will focus his quest to trim the time still further in the build-up to next year's Tokyo Olympics.
Peaty said: "This is still very special to me, winning a World Championship title and faster than I've ever done it before.
"It's obviously a little bit slower than (Sunday) night as I made a tiny little error with speed on the first 50. But I think the most important thing going into next year is I'm still learning about myself.
"I'm very happy. With that constant expectation I put on myself there is a little bit of disappointment in me, but I think that will fuel me for next year as I want to go even faster now."
Wilby, who trains alongside Peaty in Loughborough, expressed his delight at claiming his first career world medal in a time of 58.46secs behind Peaty.
"I'm really happy," Wilby said. "After the Commonwealths and Europeans last year this was always the next major international and the one last stepping stone towards Tokyo, so I'm really happy to get that silver medal and a Britain one-two means an awful lot to us as well."
Australian swimmer Mack Horton has been sent a warning letter by the sport's governing body FINA after refusing to stand on the podium for Sunday's 400m freestyle medal ceremony.
Horton, who won the silver medal, was protesting against winner Sun Yang, who has previously served a drugs ban and currently faces a hearing at the Court of Arbitration for Sport over a decision to clear him of a further doping offence.
FINA said in a statement: "(FINA) has decided to send a warning letter to Swimming Australia Ltd and to athlete Mack Hurton (AUS).
"While FINA respects the principle of freedom of speech, it has to be conducted in the right context.
"The matter over which Mack Horton was allegedly protesting is currently under review by CAS and therefore it is not appropriate for FINA to prejudice this hearing by commenting further."