Kenyan Emmanuel Wanyonyi broke the men's 1,000 metres world record in two minutes and 11.83 seconds at the Monaco Diamond League meet on Friday.
He shaved 0.13 seconds off compatriot Noah Ngeny's previous mark set 27 years ago.
The 800 metres Olympic champion Wanyonyi finished nearly a full second ahead of Briton Jake Wightman, while Algeria's Djamel Sedjati was third.
"This was the first time I ran the 1,000m, and directly breaking the World Record makes me so happy. I want to thank the other athletes to push me to my limit," he said.
The 1,000 metres is a rarely contested event that does not feature in either the Olympics or World Athletics Championships.

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