Noah Lyles – who tested positive for COVID – had to be taken off the track in a wheelchair after coming third in the men’s 200m final.
The Team USA star missed out on a sprint double as Botswana’s Letsile Tebogo took gold with a time of 19.46, becoming the first African to win the men’s 200m title.
Fellow American Kenny Bednarek took silver in a race where Tebogo’s dominant final 50m saw him become the fifth fastest man in history over 200m as he crossed the line, beating his chest.
Previously, Lyles won gold in the 100m, and going into the 200m race, he was tipped as one of the favourites – only to come in third.
After the race, Lyles was seen being spoken to by medical staff as he lay on the floor, and eventually he was helped into a wheelchair.
“It [COVID] definitely affected my performance,” he said.
The US sprinter was taken away before he spoke to any media and was later photographed wearing a face mask.
Immediately after the race, US officials said Lyles had COVID.
Lyles said he tested positive around 5am on Tuesday morning and woke up in the middle of the night “with chills”.
“I still wanted to run. They said it was possible,” he said.
The US track federation released a statement saying it had adhered to all guidelines.
“After a thorough medical evaluation, Noah chose to compete tonight. We respect his decision and will continue to monitor his condition closely,” the statement read.
The 27-year-old said no decision had been made over the 4x100m relay.
“I want to be very honest and transparent, and I’m going to let them make the decision,” Lyles said, describing himself as being at around 90 or 95%.
Lyles had hoped to become the first American since Carl Lewis, 40 years ago, to complete the sprint double.
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But, while Lyles may have had the limelight in recent days, it was Tebogo’s night.
“I’m the Olympic champion, it’s something I have never seen in my life or dreamt of – it is an amazing moment,” the 21-year-old told reporters.
He continued: “I just came here with the little that I had in me to push through because yesterday we made it to the final, my coach told me ‘now it’s your race’.
“I knew when the gun went Kenny was going to run away so make sure just to close him down, I have that top end speed that will allow me to finish the race without getting tired, so that’s what I did, and when I saw Kenny fade I knew Noah was far, far away behind us so that means I’m the Olympic champion.
“It means a lot for everybody, the country, the continent and my family.”