Great Britain was dealt a double blow on the third morning of the World Athletics Championships after medal hopes Molly Caudery and Emile Cairess were forced out of their respective events.
Caudery sustained an ankle injury in the warm-up ahead of pole vault qualifying, while Cairess - who finished fourth in the Paris 2024 Olympic marathon - battled through heat and humidity in the Japanese capital before bowing out in the 38th kilometre as a result of the muggy conditions.
Last week, World Athletics announced that road event start times on the first three days of competition would be moved forward by half an hour, to 7.30am local time (11.30pm UK time), as a response to concerns over athlete welfare following forecasts of high temperatures and humidity.
After exiting the race early less than three miles from the finish line, Cairess said: "I tried my best. I feel I just got too hot, simple as that really, conditions were so tough, it's just really hot.
"When I stopped, I just took ages to just feel all right again. I've cooled down now, but it took a while.
"I used all the stations to be diligent with the ice and the sponges and whilst it helped, it just still got too hot. I felt pretty good the first 25k and then 30k I was still feeling good and then about 32k I just really suddenly didn't feel very good anymore.”
He added: "I did a decent amount of prep for the conditions, as much as I could balancing it with training. I've not known conditions like it, but this is only my fourth marathon. Paris was a hot one but it was more warm and this was very, very humid. I did the best I could."
The temperature was already 26 degrees celcius with 68 per cent humidity at the marathon's start, rising to 28 degrees with 54 per cent humidity by the time the event concluded at 10.04am local time.
Alphonce Simbu claimed a first-ever world athletics title for Tanzania after pipping Germany's Amanal Petros to the gold medal in a thrilling photo finish.
Both men finished in 2:09.48, but Simbu's late surge propelled him to victory by three one-hundredths of a second.
Caudery, the 2024 world indoor champion and ranked fourth heading to Japan, was seeking redemption after a disastrous Olympic debut in Paris, when she crashed out of the qualification session with a no mark.
A British Athletics statement read: "Unfortunately, Molly Caudery has been forced to withdraw from pole vault qualifying following an ankle injury sustained in warm-up."
It will come as particularly devastating news for the 25-year-old, who vowed to learn from her Olympic mistakes.
"Heartbroken... again," Caudery later wrote on social media. “Waiting for an official diagnosis but a huge thank you for all the support as always.”
In Paris, Caudery was the only entrant who elected to skip the 4.40 metres height attempt, choosing to enter at 4.55.
It was a decision that proved costly when she failed to clear the bar with her three tries, particularly after it turned out 4.40 was all it took for nine other women to advance. She cleared 4.85 metres at the British championships last month.
Elise Thorner said qualifying for the 3000m steeplechase final with a personal best was "what dreams are made of", but fellow British runner Sarah Tait - who lowered her own lifetime best by over 30 seconds this year to qualify for her first world championships - fell at a water jump less than two minutes into her heat in the event and could not continue.
Elsewhere, European under-23 champion Emily Newnham booked a place in the 400m hurdles semi-finals.
