Ugandan takes nearly two seconds off 16-year-old world record in brilliant run, as Noah Lyles wins 200m ahead of his brother
Joshua Cheptegei broke the men's 5000m world record in athletics' delayed Diamond League season opener in Monaco in front of spectators, with fans allowed in in limited numbers.
The 23-year-old crossed the line in 12 minutes 35.36 seconds, 1.99 seconds faster than Kenenisa Bekele's previous mark of 12:37.35 set in May 2004.
It was an outstanding performance from Cheptegei, whose own previous personal best was 12:57.41. The Ugandan took the lead roughly mid-way through the race, and kept his lead at the 3000m and 4000m marks.
"I think Monaco is a special place and it's one of these places where I could break the world record," he said. "It took a lot of mind-setting to keep being motivated this year because so many people are staying at home but you have to stay motivated. I pushed myself, I had the right staff with me, the right coach. I'm also usually based in Europe, but being based in Uganda with my family was actually great.
"I will for sure celebrate the world record when I get home."
Hot favourite Noah Lyles breezed to a world-leading 19.76 seconds in the men's 200m, easily winning the race by more than half a second from his brother Josephus.
It was the first time the siblings had raced each other internationally across the distance, although the pair competed against each other in high school.
"Of course I don’t think he can beat me, but that’s that brotherly rivalry right there," Noah had told the Olympic Channel before the race.
World record holder Armand Duplantis took a comfortable win in the pole vault competition.
The Swede had no serious competition after American rival Sam Kendricks withdrew from the competition, with Belgium's Ben Broeders (5.70m) some 30 cm behind his winning mark.
Duplantis had earlier only cleared 5.70m on his third try, before going over at 5.80m on his first attempt to confirm the win. He later cleared a world-best 6.00m on his final attempt, and missed three tries at 6.15m – which would have been a new world best height set outdoors.
However, there was disappointment for Olympic champion Thiago Braz of Brazil, who only managed a joint-season's best 5.50m.
In the night's early track races, there were world-leading times set in the men's 110m hurdles (Orlando Ortega), men's 800m (Donovan Brazier), women's 5000m (Hellen Obiri), men's 400m hurdles (Karsten Warholm), and men's 1500m (Timothy Cheruiyot).
Warholm's Norwegian compatriot, Jakob Ingebrigtsen, also set a new European record behind Cheruiyot in the 1500m.
His time of 3:28.68 knocked 0.13 seconds off Mo Farah's seven-year-old record set on the same track.