British marathon swimmer Jack Burnell, who was controversially disqualified at the end of the 10km open-water race at the 2016 Rio Olympics, announced his retirement on Tuesday only months before the Tokyo Games.
"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," he told the BBC.
"I've also had Covid and lots of time out of the water with my shoulder.
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I'm at a point where I'm proud of what I've achieved in my career, but I'm ready to move on.
Burnell had spoken of his struggles with depression after being disqualified for striking out at 2012 gold medallist Oussama Mellouli only metres from the finish in Rio and while battling for a medal.
He said the Tunisian grabbed his leg in a chaotic sprint that ended in "four years of hard work down the drain".
"I'll be laying in bed and I can sometimes feel his hand on my leg. At that point it sends shivers down my spine," he told the BBC a year later.
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