Gallery: The 2019 Chicago Marathon

On a typically fickle Chicago morning, with gusty winds and temperatures in the low 40's, the women's favourite and world's most in form female marathoner Brigid Kosgei put daylight between herself and the previous women's world record, beating Paula Radcliffe's 2:15:25 by more than a minute, running a blistering 2:14:04. Her efforts made even more impressive when reviewing the performances of many other elites.

Kosgei went out so aggressively that at the 6km mark she was ahead of a number of the elite men, including Americans Noah Droddy and Parker Stinson.

Radcliffe's record has stood for over 16 years - many believed the mark was simply unattainable, however Kosgei's dominant performance clearly redefines a new era in women's marathoning.

One of the other major storylines on the women's side was Jordan Hasay. Hasay has looked good over the past couple of months and sounded positive at her press conference on Friday, but pulled out of today's race after only 2 miles. While Hasay herself didn't comment, her agent Ricky Simms said Hasay had sharp hamstring pain - Hasay understandably not wanting to do any further damage ahead of the Olympic Trials in February.

At mile 14, the men's race was still wide open with a pack of 5 east African runners sitting together, lead by previous champ Dickson Chumba, and containing Lawrence Cherono, Bedan Keroki, and Seifu Tura, to name just a few.

Defending champ Mo Farah was never really in contention - at the 5k he was already off the lead pack and by mile 14 was well in arrears. Farah must now wonder what's next for his marathon future - he was disappointed by his race at the London Marathon and won't be happy to be going home with an 8th place in 2:09:58.

By the time the men's field hit Chinatown around mile 21, there had been some casualties - Dickson Chumba, who did so much of the early work, had been popped (Chumba still finished 7th). Farah was further back again, and Rupp would drop out of the race only 2 miles later.

American woman Emma Bates had a great day out, finishing 4th in 2:25:27.

With less than a mile to go, the men's race was still down to a pack of 4 runners. The conditions on Michigan Avenue were unrelenting, the strong headwinds cruelly reserved for the final two miles of the race.

Kosgei led second place Ababel Yeshaneh by over 6 minutes at this point, and the world record was a foregone conclusion. Kosgei looked calm and in control as she powered home.

The men's race came down to the wire, the second thrilling World Marathon Majors finish we've seen this year, both of them coming courtesy of Lawrence Cherono. Cherono showed again today that his kick is a moneymaker, taking a 1 second win (2:05:45) over Ethiopian Dejene Debela (2:05:46). Asefa Mengstu was third in 2:05:48.

Today however, was all about Brigid Kosgei. After winning the London Marathon in April, Kosgei ran a 64:28 half marathon last month, and today claimed the marathon world record in 2:14:04.

Kosgei ran the first half in 66:59, and ran the second half in 67:15.