Russia's Sergey Kirdyapkin won the 50km race walk Saturday in record time after one of the London Olympics' most punishing events which left several athletes collapsed in exhaustion at the finish.
Under hot sun in the British capital, the two-time world champion, 32, timed an Olympic record of 3hrs 35min 59sec to beat Australia's Jared Tallent, who took a second successive silver, by 54sec.
Si Tianfeng gave China their first Olympic medal in the 50km walk as he took the bronze, 1min 17sec adrift.
The fast pace told as Japan's Koichiro Morioka, finishing 10th, was one of a number of competitors who had to be helped off and treated for overheating and dehydration at the finish near Buckingham Palace.
Kirdyapkin is the first Russian winner since 1992, when Andrey Perlov triumphed for the Commonwealth of Independent States.
He succeeds disgraced defending champion Alex Schwazer, who was withdrawn from the Italian team before the Olympics for failing a drugs test.
"I came here to win the gold medal, breaking the Olympic record just happened," said Kirdyapkin, who was visibly moved on the victory podium.
"I am very happy. I can't put it into words at the moment. I only have emotions.
"The team worked together well, but it was me that wanted to win the most. It doesn't mean I am better (than them)."
Tallent may gain revenge later as his wife Claire competes in the 20km walk where Kirdyapkin's spouse, Anisya, also takes part.
The Australian said that despite not winning, it was a special moment to bring his Olympic haul to three medals, after his 50km silver and 20km bronze in 2008.
"I tried to stay focused throughout and bring it home," said the 27-year-old. "The Olympic Games is pretty special for me. To get my third Olympic medal is pretty special. Kirdyapkin really showed his class today."
Si was ecstatic at earning reward for a sport he described as brutal.
"I am proud of myself, no pain no gain as they say!" he said.
Around a dozen athletes had formed the early lead group with 2007 world champion Nathan Deakes and Tallent among three Australians in the bunch.
However, all three talented Russians were up with them, including Kirdyapkin and reigning world champion Sergey Bakulin.
Also there were two Guatemalans including Errick Barrondo, whose silver medal in the 20km walk had been his country's first ever at an Olympics, along with fancied Frenchman Yohann Diniz, the two-time European champion.
Bakulin upped a gear at the 25km mark and the lead group shrank to eight, comprising Deakes and Tallent, the other two Russians, Diniz and the two Guatemalans, although Jaime Quiyuch was one warning away from being disqualified.
Quiyuch's walk on the wild side came to a sad end just after the two-hour mark when the judge raised the red card, prompting him to raise his hands in shock, then burst into floods of tears.
It was Si who blew the race apart as he produced a burst just after the 30km mark, and in double-quick time wiped away the 20-second gap between himself and the lead group of five.
Such was his momentum he surged on to open an eight-second lead over the five.
Barrondo's lack of experience at the distance, in which he only made his debut this year, told and he dropped away while Deakes's hopes of bowing out with an Olympic title also ended as he too lost touch.
Tallent, though, found a second wind and joined the chasing group, passing Diniz, who was already struggling when he tripped over a hoarding and fell, dashing his medal hopes.
While Tallent was in pursuit of the Russian trio, Kirdyapkin came alive and joined his compatriots in reeling in Si with 10km to go.
Tallent bided his time and then swept past tiring athletes including Si. But he could not get within striking distance of Kirdyapkin, and contented himself with saluting the crowd on the final lap.