Scotland’s Callum Hawkins collapsed just over one mile from the end of the marathon at the Commonwealth Games when leading by almost two minutes.
In hot conditions on the Gold Coast, Hawkins looked set for gold but he began weaving across the road before falling over the kerb.
He continued for another couple of hundred metres before collapsing again, hitting his head on a roadside barrier.
Australia’s Mike Shelley won the race but all thoughts were with Hawkins.
It took a couple of minutes for any medical staff to attend to the Scotsman, who was lying on the road in clear distress.
BBC Sport commentator Steve Cram said it was “a disgrace” that it took so long for any paramedics to attend to Hawkins.
Cram added: “I’m just concerned for his welfare. He hit his head on the barrier. I’m sorry if you’re watching this at home, it’s really distressing. He’s going to hurt himself and there’s nobody anywhere near.
“We should have some more medical attention. This is a guy in real distress and someone needs to recognise it for his health at this point.
“Where on earth is the help? You cannot just wait at the finish line. They’ve got radios. And finally somebody arrives. I think it’s disgraceful.”
Shelley ran past the stricken Hawkins just as help arrived and the Australian went on to claim the victory with Uganda’s Munyo Solomon Mutai in second, with Robbie Simpson of Scotland claiming the bronze.
Hawkins was eventually helped into an ambulance and a statement from Team Scotland said he was “receiving medical treatment”.
He was not the only athlete to suffer in the conditions – Tanzania’s Stephano Huche Gwandu was put in a wheelchair after falling as he crossed the finish line.
His team-mate Saidi Juma Makula collapsed close to the finish line – one of seven of the 24 starters who did not complete the race – and was helped into an ambulance.
More to follow.