Kenyan Lawrence Cherono won the Chicago Marathon as Britain’s Mo Farah failed to keep pace and finished eighth.
Cherono, 31, who also won the Boston Marathon, outsprinted Ethiopians Dejene Debela and Asefa Mengstu who were second and third.
Farah, 36, who won this race last year, finished more than four minutes adrift in two hours, nine minutes, 58 seconds.
Fellow Briton David Weir was second in the men’s wheelchair race, behind defending champion Daniel Romanchuk.
It was Farah’s slowest marathon run, by more than one minute, in six attempts and came following a challenging week after former coach Alberto Salazar was banned for four years for doping violations.
Farah, a four-time Olympic champion over 5,000m and 10,000m on the track, has never failed a drugs test and told journalists before the race there is an “agenda” against him.
Winner Cherono said: “It was a very competitive race even right from the beginning.
“Towards the end I felt like I could kick forwards, I still had enough energy to sprint and it’s amazing.
“I am so happy. It’s my second major marathon and to come only a few months after Boston is brilliant.”