Kenya’s Brigid Kosgei eclipsed the 16-year-old women’s marathon world record held by Britain’s Paula Radcliffe as she retained her Chicago title.
The 25-year-old recorded a time of two hours 14 minutes 04 seconds, easily inside Radcliffe’s mark of 2:15:25 set at the London Marathon in 2003.
It adds to the Kenyan’s win in London this year when she clocked 2:18:20 and became the youngest winner of the race.
Ethiopa’s Ababel Yeshaneh was second in Chicago, six minutes 47 seconds behind.
Only 22 runners in the men’s race finished faster than Kosgei, whose time would have been a men’s world record in 1964.