World record holder and two-time London Marathon champion Brigid Kosgei has been forced to withdraw from Sunday's race due to a minor hamstring injury, organizers said on Monday.

Kosgei, who won the London Marathon in 2019 and 2020, was one of the favorites going into the event. She also won the Tokyo Marathon earlier this year after taking home a silver medal at the Olympics last year.

"I have been struggling over the past month with an issue in the hamstring of my right leg. My training has been up and down and not the way I would like to prepare to be in top condition for the 2022 TCS London Marathon," she said in a statement.

"We've decided it's best I withdraw from this year's race and get further treatment on my injuries in order to enter 2023 stronger than ever."

Kosgei set a world record time of 2:14:04 in Chicago in 2019. She was upset in London last year when she finished fourth in a race won by her compatriot Joyciline Jepkosgei, who is set to headline the event this weekend.