Faith Kipyegon set a new world record in the 1,500m at the Florence Diamond League meet on Friday, with Britain’s Laura Muir coming in a distant second.
Muir was 10 meters behind world and Olympic champion Kenya, 29, heading into the final lap.
Kipyegon scored a clear streak to win in 3 minutes 49.11 seconds, breaking the 3:50 barrier for the first time, while Muir ran a season’s best 3:57.09.
The previous record was set by Ethiopian Genzebe Dibaba 3:5
Ireland’s Ciara Magian also achieved a season’s best time, finishing fourth with a time of 4:00.95.
Kipyegon has won world and Olympic gold on two occasions, but this is the first time she has broken a world record.
She now holds the first and third fastest times in history, running her previous best of 3:50.37 last August.
Former 200m world champion Dina Asher-Smith had to withdraw from the women’s 100m moments before the race after suffering a cramp in her hamstrings.
“Other than that’s all fine, but I didn’t want to risk anything today,” she said on social media.
“Frustrating because I was so excited to race, but I had to make a sensible call to the bigger picture.”
Britain’s Imani Lara Lansicott finished third with a time of 11.16 seconds, behind Marie-Josée Ta Lou of Ivory Coast (10.97) and Germany’s Gina Luickenkemper (11.09).
World champion Fred Curley has again been denied a meeting with Olympic champion Lamont Marcel Jacobs in the men’s 100m because the Italian has not recovered from a stroke. The back problem that forced him out of the Diamond League meeting last Sunday in Rabat
Curley has not lost this season, winning in 9.94 from Kenya’s Ferdinand Umaniyala (10.05) and fellow American Trevon Bromell (10.09).
Meanwhile, Irion Knighton claimed victory in the men’s 200m with a season’s best of 19.89.
The 19-year-old American, who holds the under-18 and under-20 world records, finished ahead of Trinidad and Tobago’s Jeremy Richards (20.28) and Canada’s Aaron Brown (20.31).