For a few moments on Sunday Kishane Thompson was an Olympic champion, to viewers in the United States at least.

As the athletes crossed the line in an incredibly close finish to the men’s 100m, NBC’s Leigh Diffey immediately called the race for the Jamaican.

“There’s an Olympic gold medal waiting for somebody, who wants it the most? Now Thompson starts to wind up,” said Diffey on NBC’s broadcast. “Kerley’s going with him. This is close. Jamaica’s going to do it! Kishane Thompson is a gold medalist!”

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Except he wasn’t. Broadcasters such as the BBC in the UK declined to name a winner until the results of a photo finish came through. And when they did, USA’s Noah Lyles was declared the new champion.

On Monday, Diffey apologized on X for his error.

“The men’s 100 was epic & closest of all time! My eyes & instinct told me Kishane Thompson won,” he wrote. “Obviously, that wasn’t the case. I shouldn’t have been so bold to call it, but I genuinely thought he won. I got it wrong. I am thrilled for @LylesNoah as his story only gets bigger!”

Diffey, who grew up in Australia before moving to the UK and then the US to pursue his career, covers motorsport as well as the Olympics for NBC.

Diffey wasn’t the only person to think Thompson had won. Lyles himself admitted he thought he had been edged into silver in a race decided by by a tiny margin.

“After the race, we were waiting for the names to pop up and I’m going to be honest, I came over, I was like ‘I think you got the Olympics, dawg.’ He was in lane 4, I was in lane 7, so I couldn’t really see what was happening,” Lyles said after the race. “I continued to run like I would win it. Something told me: ‘I need to lean.’ It is that type of race. It was crazy.”

There will be other chances for Diffey to get Lyles’s finishing position correct. The American is also going for gold in the 200m, 4x100m and possibly the 4x400m this week.