Marathon swimmer Jack Burnell has decided against bidding for a place at the Tokyo Olympics and retired at 27.
Burnell, who is a three-time World Cup winner and was controversially disqualified at Rio 2016, had been expected to race in the Tokyo 10km Olympic qualifier in May.
However, after struggling with a shoulder problem and finishing 24th at last month's Doha World Cup, he has decided to end his career.
"I want to do it on my terms," he said.
"That race was a bit of an eye-opener and, although it wasn't the only reason, it did highlight that I'm not quite there physically or mentally right now.
"For some it's the love of the sport which keeps them going even when they're past their peak, but for me it's always been about winning and I need to do what makes me happy."
Burnell came fifth at the 2015 World championships and fourth two years later despite revealing he had struggled with depression following his disqualification in the closing stages of the 10km race at Rio 2016 when he was in medal contention.
A 12th-place finish at the 2019 World Championships meant he missed out on an automatic place at the Tokyo Olympics by just two positions.
"I knew that physically Tokyo 2020 was pushing it for me, so when the Games were pushed back a year it was a big hurdle to get over," the former European medallist, told BBC Sport.
"I've also had Covid and lots of time out of the water with my shoulder and I'm at a point where I'm proud of what I've achieved in my career, but I'm ready to move on."
The Olympian will swap Loughborough for London in the coming weeks and plans to expand his performance mindset business, which sees him work with several professional footballers.
The Tokyo Olympic marathon swimming - previously known as open water swimming - qualifier will take place in the host city at the end of May.
Great Britain can earn a maximum of one male and one female Olympic berth through the event, with athletes needing to finish in the top nine to qualify.
Burnell's decision to retire means France-based swimmer Hector Pardoe is GB's leading male contender with Alice Dearing and Danielle Huskisson leading the women's line-up.
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