Kenyan Brigid Kosgei broke Paula Radcliffe's women's marathon world record when she ran two hours, 14 minutes and 4 seconds at the Chicago Marathon on Sunday.
Kosgei broke the mark of 2:15:25 set by Radcliffe in the London Marathon on April 13, 2003 as she won in Chicago for the second straight year.
In an incredible week for competitive running, it comes just a day after fellow Kenyan Eliud Kipchoge made history as first person to run sub two-hour marathon.
"I was not expecting to run like this," Kosgei said. "They [spectators] were cheering, cheering and I got more energy to keep faster."
Kosgei, the 25-year-old who won the London Marathon in April and clocked the fastest half-marathon in history this year of 1:04:28, quickly separated herself from the women's field as she ran with two male pace-setters.
She crossed the finish line alone, with Ethiopians Ababel Yeshaneh and Gelete Burka a distant second and third in 2:20:51 and 2:20:55.
Radcliffe was on hand to witness the fall of her record. "When I saw how fast Brigid was running in the first part of the race, if she was able to hold that together, she was always going to beat the time," she said.
Kenya's Lawrence Cherono won a men's race that came down to the wire in 2:05:45 – barely edging Ethiopia's Dejene Debela who was second in 2:05:46 with Ethiopian Asefa Mengstu third in 2:05:48.
Last year's winner, Mo Farah of Britain, finished a distant eighth in 2:09:58.
The race was the first for Farah since his former coach Alberto Salazar was banned from the sport for four years by the U.S. Anti-Doping Agency for “orchestrating and facilitating prohibited doping conduct”,
Salazar has said he plans to appeal against the ruling.