Kenya's Brigid Kosgei has set a new women's marathon world record time of two hours, 14 minutes and four seconds in Chicago, beating Paula Radcliffe's best which was set in April 2003, while Ireland's Fionnuala McCormack secured a place at Tokyo 2020 as she crossed the line in a personal best of 2:26:47 to finish fifth.
The two hours, 15 minutes and 25 seconds Radcliffe recorded in London 16 and a half years ago had proven unbeatable until 25-year-old Kenyan Kosgei ripped up the record books.
She went through the halfway point in 1.06.59 and barely fell off the pace as she pressed on.
Radcliffe was present to congratulate Kosgei at the finish, with her record beaten by well over a minute.
McCormack’s time was the second fastest ever by an Irish woman, with only Catherina McKiernan having clocked a better time.
Kosgei's achievement comes on an incredible weekend for marathon running, with Eliud Kipchoge breaking the two-hour barrier - albeit not under race conditions and therefore not a record - on Saturday.
Kosgei's compatriot Lawrence Cherono sprinted past Ethiopia's Dejene Debela to win the men's race.
Cherono clocked 2:05:45 to add Chicago to his Boston Marathon title.
Debela was a second back as British defending champion Mo Farah was eighth in 2:09.58 and Galen Rupp failed to finish.
The race was the first for Farah and Rupp since their former coach Alberto Salazar was banned from the sport for four years by the US Anti-Doping Agency for "orchestrating and facilitating prohibited doping conduct".