Australia's Mike Shelley passed the prone Hawkins and retained the marathon title he won in Glasgow four years ago in two hours, 16.46 minutes.
I wasn't sure what was going on, I had a couple of mates around Main Beach who said Callum was in a bit of trouble," Shelley said. "They told me to keep going and gave me encouragement.
"I saw him [Callum] on the Sundale Bridge and thought, 'Oh s***' and just tried to hang on. When I was coming down the home straight I tried to accelerate but I was just gone.
"I'm glad to be finished, to be honest. I thought hopefully I can get to the finish line because I was starting to get cramps in my hands."
It's been a day we'll never forget, and 🇦🇺 @MShelley42km leaves his mark with gold 🥇 in the men's marathon. A colossal effort on the Gold Coast.@maccas #GC2018 #ShareTheDream pic.twitter.com/VK2wCWLOib — 7CommGames (@7CommGames) April 15, 2018
Helalia Johannes of Namibia won the women's marathon in two hours, 32.40 minutes, crossing the line 43 seconds ahead of Australian Lisa Weightman.
Weightman's compatriot Jessica Trengrove took bronze for the second Games in a row to add yet another medal to the host nation's already impressive tally.
Hawkins held a lead of almost two minutes after two hours of running in blazing sun and temperatures of 28 degrees Celsius (82F) on the roads of the Gold Coast when he was unable to continue, weaving across the road before collapsing.
The 25-year-old managed to get up and run another 100 metres or so but collapsed again just before the 40-kilometre marker, lying on the road in clear distress.
People watching the race on TV took to social media to express their outrage at the time it took to get medical attention to the Scot, reserving particular ire for those spectators taking photos of Hawkins.
Callum Hawkins of Scotland is given assistance as he collapses in the Men's marathon. (Getty) Source: Getty
Former athlete Steve Cram, commentating for the BBC, said it was a "disgrace".
"Where on earth is the help?" he said. "You cannot just wait at the finish line. They've got radios... I think it's disgraceful."
Team Scotland later said Hawkins had been taken to hospital for treatment, as is normal procedure in such cases, and there were "no major concerns at this stage".
Mark Peters, chief executive of the local organising committee, said they would be investigating whether there had been an excessive delay in getting help to Hawkins.
"You can't have medical people on every kilometre of the race," he said.
"So they are professionally positioned the same as for our Gold Coast marathon, where we have 30,000 people. Obviously, the health of the athlete is absolutely prime.
"Sometimes the medical people arrive and the athlete has to make a decision as to whether they go on or not and I understand that was a part of the discussion.
"Incredibly, athletes in whatever state they are want to finish and we've seen that in other marathons."
Peters said he did not think the conditions had been too brutal for the race to go ahead.
"Athletes run in snow, they run in 30 odd degrees heat so we don't think that's an issue," he said.
"Unfortunately, these incredible athletes sometimes run themselves to exhaustion and there's rarely a marathon where somebody doesn't collapse."
