David Weir came through the hardest race of his life to complete a golden quadruple on the final day of London 2012 and end a stunning summer of sport in style.
The 'Weirwolf', released on to the sunny streets of the capital after a week of track domination, felt he was wilting in the near 30 degree heat just five miles into today's marathon as his punishing schedule threatened to take its toll.
But, urged on by the cheers of thousands of fans lining the looped city-centre course, he dug as deep as he could go before timing his sprint finish to perfection down The Mall.
Victory sealed a clean sweep and a week to remember for the 33-year-old, who added a fourth title to his T54 800m, 1500m and 5,000m crowns and confirmed his status as one of the heroes of the Games.
And more British success was to follow as Shelly Woods, in contrast to Weir looking to make up for three successive disappointments in the Olympic Stadium, claimed silver in the women's event.
"It was tough, the first five miles I was absolutely dying to tell the truth," said Weir, a six-time London Marathon winner.
"I didn't think I was going to manage to cope, with the heat and everything. I felt flat.
"I had to just dig deep and have another energy shot that I took with me just to get me going. That was meant for about 16 miles, not the first five miles, but I'm glad I took it on board. It just gave me a bit more energy.
"That was the toughest race I've ever raced in my life.
"They were all working together to try and stop me, but I'm used to that. I do my own thing and race as best as I can."
The Londoner finished in one hour 30.20 minutes, just a second ahead of silver medallist Marcel Hug and Australian defending champion Kurt Fearnley, who won bronze.
The home favourite was in a six-man breakaway group which established an early lead. Three Japanese racers who had been in contention dropped off with three miles to go, leaving the leading three to fight it out for the medals.
Weir was riding the crest of the wave, though, Hug admitting last week his rival was "flying", and there only ever looked like being one winner again when the trio turned into the finishing straight.
"I didn't know where the finishing line was, that's why I looked a bit moody crossing the line," added Weir, who has been training under the guidance of his coach Jenny Archer alongside cyclists in Richmond Park.
"I didn't know if it was the first line, the second line, because there was no tape. I didn't know how close they were behind me.
"I had to really dig deep and I knew that I had lots of top speed. My speed coming down there was 23.5 (miles per hour) so I knew I had to just carry on until my arms couldn't feel the push rims any more and cross that line.
"I was flat out from when I came round the last bend, I sprinted as hard as I could. I thought I went too early, but my arms didn't feel tired."
He was cheered across the line by his heavily pregnant partner Emily Thorne - "I hope she hasn't given birth," he said afterward - and celebrated after his medal presentation with their one-year-old son Mason on his lap.
He reckoned he had about "50 or 60" friends and family from the Roundshaw Estate in south London where he lives.
"The crowd were just awesome," he said. "I've never seen that before for the whole race. It was fantastic, they give you a lift.
"My whole body was tingling. When I couldn't even feel my push rims it was getting me through."
London 2012 chairman Sebastian Coe hailed Weir, who now has six career Paralympic golds, saying: "He has just had a majestic Games. He is a phenomenal athlete."
Woods too required plenty of character to rescue a Paralympics which was fast turning into a nightmare.
She was unable to get close to a medal in the 1500m and 5,000m and did not even reach the final of the 800m, but produced a strong finish to ensure a podium place did not pass her by in the marathon.
Coming into the home straight in a breakaway group of four, she held off Sandra Graf of Switzerland, who took bronze, and Amanda McGrory of the United States. American Shirley Reilly had just too much for Woods and won in 1hr 46mins 33secs, a second ahead of the Briton.
"I am so proud of myself," Woods said. "I've had such a tough week on the track. I kept getting bashed down and I kept jumping up for more and today I jumped up for more.
"It was such a tough race, probably one of the hardest marathons I've ever done. I've got blisters, but it's 100% worth it and something I'll remember for ever."
Great Britain's athletics team finished with 11 gold medals and 29 in total.
That put the hosts third in the athletics and the overall medals table behind China and Russia.
Elsewhere, Brazil's Tito Sena and Spain's Alberto Suarez Laso won the T46 and T12 marathons respectively.