Karsten Warholm broke the 1992 men's 400m hurdles world record of 46.78sec tonight by running 46.70 in Oslo ©Getty Images

Karsten Warholm, knocked down from second to third on the all-time men’s 400 metres hurdles list by Rae Benjamin’s clocking of 46.83sec on Sunday, responded tonight at his home Diamond League meeting in Oslo by moving up to number one - with a spectacular world record of 46.70sec.

In so doing, the 25-year-old double world champion broke the 46.78 mark set by Kevin Young of the United States in winning the 1992 Olympic title in Barcelona - the longest-standing men’s track record on the books.

Now the exuberant Norwegian will be looking with increased excitement at the second part of Young’s achievement with less than a month to go until the athletics starts at the Tokyo Olympics.

A year ago at this meeting in the Bislett Stadium, Warholm came within a whisker of the world record, surmising ruefully after clocking a personal best of 46.87 that he might have achieved his ambition but for clouting the last hurdle.

Tonight the plan finally worked perfectly as he registered his fourth, and most significant sub-47-second clocking.

"I knew that I had a fast time in my body," Warholm said.

"It feels like it has been there for a long time but you never know when it is right to do it.

"And it is one thing to know you have it in you and another to go out and do it.

"It is very special to do it here in Bislett in front of a great crowd including my friends and family.

"This is my first 400m hurdles of the season so I really think there is more in the tank.

"It might take another world record to win the Olympics.

"There are such a lot of great guys out there at the moment who will all be aiming to do it and win gold.

"I am happy that there is such great competition.

"But I now have the world record and I am so happy.

"This world record was older than me!"

Warholm was followed home by Brazil’s Alison dos Santos in a South American record of 47.38, with Yasmani Coppello of Turkey third in 48.86.

The Norwegian's time lays down a marker to the American Benjamin and all other rivals ahead of Tokyo 2020.

It was a memorable night to for Australia’s Stewart McSweyn, who won the Dream Mile event now re-named in honour of the late former Oslo meeting director and European Athletics President Svein Arne Hansen in an area record of 3min 48.37sec - the fastest time seen this year.

He was chased home by former European indoor 1500m champion Marcin Lewandowski in a Polish record of 3:49.11, with Uganda’s Ronald Musagala setting a national record of 3:53.07 in sixth place.

And there was more super-fast track action in the men’s 3,000m, where Ethiopia’s Yomif Kejelcha set a Diamond League record, personal best and 2021 world best of 7:26.25, with two Kenyans setting personal bests behind him in Jacob Krop, who ran 7:30.07, and Nicholas Kimeli, who clocked 7:31.33.

Femke Bol of The Netherlands, the European indoor 400m champion, also had a night to remember as she set a national record of 53.33sec in her specialist event, the 400m hurdles.

Sweden’s holder of the pole vault world record, Armand Duplantis - another of the sport’s glittering adornments - won with 6.01 metres from double world champion Sam Kendricks of the US, who cleared 5.91m, with France’s former world record-holder Renaud Lavillenie third on 5.81m.

Germany’s world champion Malaika Mihambo won the women’s long jump with a best effort of 6.86m and a final three-winning effort of 6.83m, with Serbia’s three-time European indoor champion Ivana Španović, back after injury, coming second with a 6.66m best and a final-three effort of 6.61m.

Kenya’s back-to-back world champion Hellen Obiri underlined her fine form as she won the women’s 5,000 metres in a season’s best of 14min 26.38sec, with Ethiopia’s Fantu Worku second in a personal best of 14:26.80, Kenya’s Margaret Chelimo third in 14:28.24 and Tokyo-bound Eilish McColgan fourth in a British record of 14:28.55, breaking Paula Radcliffe’s 2004 mark of 14:29.11.

Sweden’s world discus champion Daniel Ståhl produced by far the best effort of 68.65 metres, but only claimed victory by a countback process after both he and Slovenia’s Kristjan Ceh threw 65.72m in the final round.

"I am happy with the win but not with this system," Stahl said.

"The rule is tough on everyone."

Marie-Josée Ta Lou of the Ivory Coast won the women’s 100 metres in a season’s best of 10.91sec from Britain’s Daryll Neita, who clocked 11.06, and Ajla Del Ponte of Switzerland, who was timed at 11.16.

Kate Grace of the US won the women’s 800m in a personal best of 1min 57.60sec from Uganda's surprise 2019 world champion Halimah Nakaayi, who clocked a season’s best of 1:58.70.

Canada’s Andre De Grasse won the men’s 200m - at which he won silver behind Jamaican Usain Bolt at the Rio 2016 Olympics - in 20.09sec from compatriot Aaron Brown, who clocked 20.38, with Botswana’s Isaac Makwala third in 20.61.