Adam Peaty has tested positive for Covid-19, less than 24 hours after narrowly missing out on a historic three-peat in the 100m breaststroke.
However, the 29-year-old is hopeful of being fit to feature in the relay events in Paris, which begin later this week.
The Rio 2016 and Tokyo 2020 champion mentioned after Sunday's final that he had woken on the morning of the showpiece, which saw him finish joint-second by the barest of margins, with a sore throat and returned a positive Covid test on Monday morning.
"Adam began feeling unwell on Sunday, ahead of his men's 100m breaststroke final," a statement from Team GB read.
"In the hours after the final, his symptoms became worse and he was tested for Covid early on Monday morning. He tested positive at that point.
"He is hopeful to be back in competition for the relay events later in the swimming programme. As in any case of illness, the situation is being managed appropriately, with all usual precautions being taken to keep the wider delegation healthy."
Peaty had been aiming to win the 100m breastroke for a third successive Games, finishing 0.02 seconds behind Italy's Nicolo Martinenghi.
He was seeking to become just the second male swimmer after Michael Phelps to win the same event at three successive Olympics but Martinenghi claimed a stunning upset victory from lane seven.
His time of 59.03 seconds was two hundredths of a second quicker than Peaty, who touched the wall at the same time as America's Nic Fink, meaning they were both awarded the silver medal.
"I did as well as I could," Peaty said after the race. "It's not about the end goal, it's all about the process and it doesn't matter what the time says on the score, in my heart I've already won.
"I'm not crying because I've come second, I'm crying because it just took so much to get here.
"It was incredibly hard to win it once and to win it again. I'm trying to find new ways to do it. Everything that happened to this point I think has happened for a reason and I'm so happy that I can race the best in the world and I came joint-second."
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