Norway's Karsten Warholm has won 400m hurdles gold after shattering his own world record at Tokyo 2020.
Double world champion Warholm registered a time of 46.70 seconds in Oslo on July 1, but he has smashed that in the most important race of his career, recording a time of 45.94 in the final.
USA's Rai Benjamin, who was closest to the 25-year-old all the way, finished in an area record time of 46.17 seconds to take silver.
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Brazil's Alison dos Santos won bronze in 46.72 seconds which would have won every past Olympic 400m hurdle final.
The only doubt that Warholm may be caught was in the final 100m when he became locked in a contest with Benjamin trailing behind, but the Norwegian was able to somehow step up a further gear to win his first Olympic medal.
"It hasn't sunk in but running this time is just crazy," Warholm told Eurosport's Greg Rutherford after his stunning achievement.
"My coach actually told me in training 'the perfect race can be in 45 seconds' but to do it is something else.
"We always said 'well done is better than well spoken' and today I knew that it was going to be a tough race.
I've just got to give credit to my competitors as well. Can you imagine running 46.17 and getting a silver? He deserves a gold as well.
"I told my subconscious going in 'when you get to the last hurdle put in everything you've done to reach this moment'."
Mark Gillingham said on Eurosport commentary: "The Viking roars and the double world champion is now the Olympic champion and he's bettered his own record.
"He's the first man in under 46 seconds and that is simply stunning."
Co-commentator Chris Dennis said: "That is a remarkable chunk off the world record. To give it some perspective the great Edwin Moses never broke 47 seconds.
Benjamin was looming on his inside, but the fact that Warholm decided to stick an extra stride at the last.
"He'd been loping a little bit to the penultimate hurdle which allowed Benjamin in, but then Warholm stuck in an extra stride which allowed him to run hard off that final barrier.
It is a phenomenal run. There simply won't be a performance at this Olympics that comes close to that.
RUTHERFORD: I'M LOST FOR WORDS
"An unbelievable 400m hurdles, Rutherford said after the race. "We have just seen one of the greatest athletic performances in the history of this sport.
"The man has just done sub-46 in the four hurdles. To put that into perspective he would have won the UK trials in 400m flat without the hurdles being there.
"I'm lost for words. He's already broken the world record once. To then do it again in the Olympic final, to that level I'm trying to process what I've just seen. Unbelievable.
"A great person, a great ambassador for the sport so to see that is wonderful."
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