Great Britain's Elliot Giles ran the second-quickest indoor 800m in history as he set a new British record at the World Indoor Tour in Torun, Poland.
The 26-year-old clocked one minute 43.63 seconds to beat compatriot Jamie Webb, who finished second in 1:44.54.
The British record had been held by Sebastian Coe since March 1983.
It is Giles' third victory of the series, following wins in the season opener in Karlsruhe and the tour's second meet in Lievin on 9 February.
"I'm still trying to process what even just happened. It really does feel like a blur," Giles said.
"I can't believe I just ran 1:43 indoors. I can't put into words right now how it feels. I'm so overwhelmed by it all. It feels like I'm on cloud nine."
It is another personal best for Giles following his 1:45.49 in France last week, and in history is only bettered by Wilson Kipketer's indoor world record of 1:42.67.
Webb, 26, also ran within the record previously set by Coe as he too clocked a personal best.
Wednesday's meet in Torun was the fourth event of the World Indoor Tour series, with the final leg taking place on 24 February in Madrid, Spain.
In addition to a $10,000 victory bonus for the Tour winner in each discipline, the winner will also receive a wildcard for the 2022 World Indoor Championships in Belgrade.
You can watch live coverage of the 2021 World Athletics Indoor Tour on the BBC Sport website, BBC iPlayer and the BBC Red Button.
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