Mo Farah hailed his 5,000 metres victory as his sweetest yet as he completed a dream double-double at the World Championships.
The 30-year-old sealed his status as arguably the greatest British athlete of all time, producing a trademark lung-bursting kick down the home straight at Moscow's Luzhniki Stadium to claim a thrilling 5,000 metres gold, six days after racing to glory over 10,000m.
He added the titles to his twin Olympic triumphs to become only the second man after Ethiopian great Kenenisa Bekele to win both long-distance crowns at the Olympics and the World Championships.
"It (this win) was definitely the sweetest, by far," he said. "Earlier in the race I had a stitch and it was important I got over that. My legs felt all right, but they were a lot more heavy than the rest of the guys.
"I thought the race would have gone harder, but it suited me today.
"I was confident, from having run a fast 1500m (he broke the European record over the distance in Monaco last month) and a couple of other fast races, that if it came down to the end I would be able to come home strong.
"You've got to respect the other guys, but you just want to be able to keep winning."
His rivals did once again play into his hands with the slow pace, the Briton unleashing his kick with around 650m to go.
It looked at one point as if he might be caught, with several men still in contention coming into the home straight, but Farah, his face contorted with effort, dug into his deepest reserves of energy to pull away and win by 0.28 seconds.
He crossed the line in 13 minutes 26.98 seconds, with Ethiopia's Hagos Gebrhiwet taking silver and Kenya's Isaiah Kiplangat Koech the bronze.
After a typically rapid final lap, timed at 53.51s, he dropped to his knees and kissed the blue Mondo track before embracing coach Alberto Salazar, the man who has overseen Farah's rise to greatness.
Victory took Farah's tally of global gold medals to five, having also won the 5,000m two years ago in Daegu.
Farah said: "It's amazing, only the great Kenenisa Bekele has achieved so many things. To be able to achieve what he has achieved is just an honour.
"I enjoyed tonight and now I'm looking forward to a bit of time off and spending it with the family. I never thought in my career that I'd be able to achieve something like this, anything is possible I guess."
He received his gold medal from Sebastian Coe, who won his first Olympic title in this very stadium.
Farah and his American training partner Galen Rupp were the only two athletes attempting the double, leaving their fresher rivals with a distinct advantage.
UK Athletics head of science Barry Fudge had said victory for the 30-year-old would be a "long shot" because of the toll winning the 10,000m crown would have taken on his body.
He managed it in London last summer, but on that occasion he had one extra day to recover.
Farah, though, is no ordinary athlete. Five athletes in the field had faster personal bests than him and seven had gone quicker than him this season, but they simply cannot find a way to beat him on the big stage.
Olympic 10,000m bronze medallist Brendan Foster told BBC Sport: "For my money he is the greatest athlete we've ever had in this country. He put himself at the front and he would not let them past."
The only thing now missing from Farah's resume is a world record. Bekele holds both over 5,000m and 10,000m with times of 12:37.35 and 26:17.53 respectively.
"I would like to run a decent time, but for me the most important thing is trying to win medals," he said.
"It would be nice to get closer to the record and the great athlete Bekele has both records. It would be nice to get closer to that, but I haven't tried too much.
"I've just been concentrating on the World Championships and winning medals for my country. But now it gives me time to think about it and try to prepare for it. That's very hard in a championship, when you have to cover every move."