Extreme heat and humidity saw 28 of the 68 starters fail to finish in the women’s marathon at the World Championships in Doha.
The midnight start saw a temperature of 32.7C and a humidity index of 73 per cent for the 26.2 miles (42.195 km) course which was at the limit of what the International Association of Athletics Federations (IAAF) deemed acceptable.
But by the time Kenya's Ruth Chepngetich crossed the finish line two hours, 32 minutes and 43 seconds later it was still 31C, 77 per cent humidity and not a breath of wind.
Understandably Chepngetich clocked the slowest ever time for the win, with Bahrain's defending world champion Rose Chelimo more than a minute adrift in second and Namibia's Helalia Johannes completing the podium for third.
On the race, Chepngetich said: "It was very hot. In this weather I lost my mind, to win it was not easy and I thank God for the tactics that he gave me."
Johannes added: "This is the hardest thing I did because I never run in this terrible weather.
"I won the [Commonwealth] gold medal last year at the Gold Coast but the Gold Coast's weather was better than this one. This one it's horrible. It's hot."
Many athletes needed medical attention, with some going as far as saying the conditions were so severe the race should not have been run.
"The humidity kills you," said Volha Mazuronak of Belarus. "There is nothing to breathe. I thought I wouldn't finish. It's disrespect towards the athletes.
"A bunch of high-ranked officials gathered and decided that it would take [the championships] here but they are sitting in the cool and they are probably sleeping right now."
Despite the conditions, there was no cases of heat stroke reported with the IAAF claiming the completion rate was comparable to previous races.
In a statement, the IAAF said: "In the women's marathon 68 competitors started and 40 finished - which is comparable to the completion rate at previous World Championships in Tokyo (1991) and Moscow (2013).
"Thirty athletes visited the medical centre as a precaution. A small number were kept under observation and one athlete was referred to the hospital for observation but later released."