Karsten Warholm set a new 300m hurdles world record at the Impossible Games in Oslo's Bislett Stadium on Thursday (11 June).
Running against the clock in lane seven in front of a tiny crowd due to COVID-19 restrictions, the two-time reigning world 400m hurdles champion surged out of the blocks and clocked 33.78s, a massive seven-tenths of a second inside the previous best.
Team Ingebrigtsen won the second star event on the track, the men's team 2000m, over Team Cheruiyot running at the same time in Nairobi.
Leading the way was double European champion Jakob Ingebrigtsen who set a new European record.
World record holder Mondo Duplantis won the men's pole vault in a thrilling virtual duel with London 2012 gold medallist Renaud Lavillenie.
Warholm delivers in Oslo
Karsten Warholm's attempt was the headline act at the made-for-TV event which featured rarely-run distances and races from different venues.
The home favourite competed alone in the 300m hurdles and started quickly, appearing to overstride like a long jumper as he headed to the first obstacle.
While the stride pattern was different from in his usual event, the 24-year-old was able to push hard on the flat and measure his hurdles to perfection with his stamina enabling him to keep going all the way to the line.
His time was 33.78s, seven-tenths inside Chris Rawlinson's mark set in June 2002, on his first competitive appearance of the season after the onset of the COVID-19 pandemic.
Filip Ingebrigtsen won twice in an hour although it was younger brother Jakob who ended up stealing the limelight.
The middle of the three siblings made a record-breaking start to the night's action on the track, bettering 1996 Olympic 800m champion Vebjorn Rodal's Norwegian 1000m record.
Assisted by three pacemakers, Filip was left alone at the end and clocked 2:16.48, three-tenths of a second inside the old mark.
Those exertions told later in the Maurie Plant Memorial Race, named after the late Australian agent and commentator.
The Ingebrigtsens and two other Norwegians made up Team Ingebrigtsen in Oslo with Team Cheruiyot, featuring five members of the Rongai Athletics Club including reigning world 1500m champion Timothy Cheruiyot and 2017 winner Elijah Manangoi, running inside Nairobi's Nyano National Stadium.
As well as racing at an altitude of almost 2,000m, the Kenyans had to deal with wind and rain and were always behind the 'home' team.
With the aggregate times of the first three to cross the line deciding the outcome, Filip had to try and keep up with Jakob and Henrik Ingebrigtsen.
He did his bit but, up front, Jakob stopped the clock in 4:50.01, breaking Steve Cram's European record as the Briton commentated on the event for worldwide audiences.
The pole vault saw the top two men in history, Renaud Lavillenie and Mondo Duplantis go head-to-head but not in person.
London 2012 gold medallist Lavillenie was actually able to watch the events unfold on television with his pre-recorded jumps from Tuesday, in his back garden in Clermont-Ferrand, integrated into the live competition.
Lavillenie had two failures at both 5.36 and 5.51, but soon warmed to his task and was delighted with his first-time clearance at 5.81m.
Duplantis, who took Lavillenie's world record in February before going even higher with 6.18m in Glasgow, responded immediately before both men failed twice at 5.86m.
The Frenchman never looked like clearing the height with his short run-up at home, but Duplantis succeeded on his third and final attempt to take the victory.
World champion Daniel Stahl took the men's discus with a fifth-round throw of 65.92m ahead of fellow Swede Simon Pettersson.
Rio 2016 400m hurdles silver medallist Sara Slott Petersen won a high-class women's 300m hurdles, edging out Norway's Amalie Iuel in 39.42s.
Switzerland's reigning 400m hurdles European champion Lea Sprunger was back in third after struggling with her stride pattern early on.
There was a Norwegian record in the rarely-run women's 200m hurdles courtesy of Line Kloster.
The 400m hurdles specialist ran 26.11 with Annimari Korte, who clocked the quickest 100m hurdles in the world this year in Lahti on Sunday, third behind her fellow Finn Nooralotta Neziri.
Olympic cross-country skiing gold medallist and 10-time world champion Therese Johaug broke her own personal best in the women's 10,000m.
The 31-year-old, who won the Norwegian title at the distance last August, ran solo and broke the tape in 31:40.67.
And in the shot put, Marcus Thomsen took victory with a new lifetime best of 21.03m.