Mo Farah delivered on all the huge pre-Games hype with a fantastic run to become Britain's first 10,000 metres Olympic champion in front of an ecstatic home crowd.
The 29-year-old took the gold medal with a time of 27 minutes 30.42 seconds, half a second ahead of his American training partner Galen Rupp who grabbed a surprise second place.
Ethiopia's Tariku Bekele claimed bronze with his older brother Kenenisa, who was bidding for an unprecedented third 10,000m Olympic gold, in fourth.
"The best moment of my life, something I've worked so hard for," said Farah, who had dropped to his knees in elation after crossing the line.
"My legs were getting tired and I had to dig in that last bit. But the crowd helped me to get through. Unbelievable. My childhood, my coaches, I can't thank enough people."
"I just can't believe it, the crowd got behind me so much. I've never experienced anything like this" - Mo Farah
On a balmy night for British fans, Farah grabbed a third athletics gold medal for the host nation, a haul they have never achieved before in one day.
The 25-lap race had been a nervy one up until the final lap when Farah broke away. To deafening cheers he found an extra burst of energy on the last bend that took him over the line to raucous applause.
For Farah, 5,000m European and world champion and 10,000m European champion, Saturday's victory over the longer distance was all the sweeter after letting the 10,000m world title slip from his grasp in South Korea last year where he was pipped on the line and forced to settle for silver.
The man who moved to England from Mogadishu, Somalia at the age of eight will have a chance of double gold in London as he is also down to run the 5,000m.
His profile has rocketed since moving from leafy west London to America in 2011 and switching to a new trainer in three-times New York marathon winner Alberto Salazar.
"Seeing my daughter was so emotional. Coming out running to me, wow," Farah said, having rushed to embrace his daughter and pregnant wife on the track to huge cheers.
Rupp, who became the first American to win a medal in the event since Billy Mills won it in 1964 in Tokyo, was delighted for his training partner.
"I'm thrilled for Mo. It's unreal. Two training partners coming in first and second, I couldn't be happier. I wouldn't be where I am today without him," Rupp said.
"We work hard. I'm the lucky one - I get to train with the best middle-distance runner in the world."