Adam Peaty on for Paris with year's fastest 100m breaststroke time
The world record holder had set a time of 58.53, the year's best until the evening final, in the heats at the London Aquatics Centre.
The Briton had to settle for bronze at the world championships in Qatar last February, with American Nic Fink winning in 58.57. Peaty's world record, set in Gwangju in 2019, stands at 56.88.
The selection time for Paris was set at 59.45, with second-placed James Wilby finishing in 59.47.
"There's still a lot to come there," Peaty told BBC television after his fastest time since he won gold at the Tokyo Olympics.
"This morning I was like, I'm actually so grateful for coming back here, and I didn't give up... we're coming back and I'm happy with that.
"I woke up today and it was like, I'm blessed, I'm healthy, I've got good talent and I just want to race the best in the world. That's a good job to have. You've got to put it in perspective."
He has been open about depression and drinking problems in the past and missed last year's world championships in Fukuoka while taking time out from competition for mental health reasons.
He returned with modest results at a trio of World Cup events in October as he started to build up towards Paris, where he will chase an unprecedented third successive 100m breaststroke title.
China's Qin Haiyang won the 50m, 100m and 200m breaststroke titles in Fukuoka last July and has emerged as a favourite for Paris.
He swam the 100m in 57.69 in Fukuoka last July and also at a World Cup meeting in Berlin last October, the fastest time ever by anyone other than Peaty.
