South African swimmer Chad Le Clos revealed on Thursday he had suffered a training injury ahead of a Paris Games the former Olympic champion has presented as unfinished business.
The 32-year-old, who beat US giant Michael Phelps to 200 metres butterfly gold at London 2012, is at his fourth Games and seeking a return to the medals after drawing a blank in Tokyo three years ago.
Describing himself as "a bit of a pensioner" after taking his first short course world championship in 2010, South Africa's most decorated swimmer said his body had taken a few knocks along the way and the latest very recently.
"I had a bit of an incident," he said of a training mishap. "I had a small tear in my upper trap, this is 16 days ago, but everything is good. I'm lucky to have amazing doctors and physios in the national team.
"We're doing everything we can. I've had a great, great camp and I'm in fantastic shape. May the best three guys win on the day."
Le Clos, who will swim the 100 butterfly, said he had "let go of the past" and planned to go on to the 2028 Los Angeles Games.
"I believe I will be in LA," he said at a World Aquatics press conference with other athletes. "Maybe not as competitive but we'll see what happens.
"I look at my last couple of Olympics, London was hugely successful, Rio I got the two silvers and I got that fourth in a fast race (200 butterfly) which I still believe was the worst race of my career," he added.
"The next year I won the world title in Budapest in a faster time so for me that was my redemption... this Olympics is just about, not going out on my terms but swimming the best that I can be."