Jepkosgei has raced just once this year, placing seventh at the Boston Marathon in April, but her past record underlines her status as a formidable opponent. She won in London last year in 2:17:43, her second victory in a marathon major, having also won in New York in 2019.
Yehualaw and Jepkosgei have clashed just once before, at the 2020 World Half Marathon Championships in Gdynia, where Yehualaw finished three places ahead of the Kenyan. But in a non-championship race over double the distance, the outcome today could be quite different.
Former half marathon specialist Joan Chelimo Melly finally got to grips with the marathon earlier this year, setting a Romanian record of 2:18:04 to win in Seoul. She placed seventh in London last year, but is an improved runner since then.
Kenya's Judith Jeptum Korir was a late addition to the field but is still one to watch. Earlier this year she won in Paris with a course record of 2:19:48, then improved on that mark to take silver at the World Championships in Eugene, clocking a PB of 2:18:20.
Mary Ngugi's Personal Best may not be as fast as some of her rivals, but this will be her first run on one of the faster big city courses. Two successive third-place finishes in Boston underlines her pedigree.
An Ethiopian victory seems fairly likely as the five fastest athletes in the field - including multiple global champion Kenenisa Bekele and defending champion Sisay Lemma all hail from the East African nation. But recent form is important too, and Kenya's Amos Kipruto and Belgium's Bashir Abdi carry plenty of that into today's race.
Lemma, who won in the British capital last year in 2:04:01, has reached the podium in his past four marathon majors. The Ethiopian has a PB of 2:03:36 and will be keen to get close to - or improve on - that today.