The Doha World Championships were branded a “disaster” on Saturday after shocking scenes at the midnight women’s marathon, where sweltering conditions caused numerous athletes to collapse and almost half the field failed to finish.

Twenty-eight of the 68 women who started the race dropped out along the way, with many carried by stretcher from wherever they had fallen along the course to a makeshift hospital set up next to the finish line.

The race took place in the early hours of Saturday morning in an attempt to avoid the brutal heat of the day, but temperatures still exceeded 30C throughout and humidity rose steadily to well above 80 per cent.

Amid the havoc, Kenya’s Ruth Chepngetich emerged triumphant, claiming gold in two hours, 32 minutes and 43 seconds - the slowest ever World Championships winning time and more than 15 minutes slower than her personal best. The winner then collapsed some time after the race while talking to the media.

Britain’s sole entrant, Charlotte Purdue, was one of 16 athletes who failed to even reach the halfway point as conditions took their toll from the outset in a race of pure attrition. Runners were strung out from an early stage as they tried to do all they could to cool their bodies by wearing ice scarves and repeatedly tipping cold water over their heads.