Bolt slowed up crossing the line as he led a Jamaican 1-2-3 in the men's Olympic 200 metres at the Olympic Stadium, raising his finger to his lips in what looked like a failed attempt to silence the 80,000-strong crowd's deafening roar.
"The guy is just on another planet right now," said fourth placed Wallace Spearmon.
Bolt's winning time of 19.32 seconds was outside his own world record, but the crowd had already been treated to the first new world mark on London's Olympic track.
An hour before Bolt's run, David Rudisha of Kenya won the 800-meters in 1 minute, 40.91 seconds, shaving one-tenth of a second off the record he set in 2010.
"Yes, he's the greatest runner," said Timothy Kitum, Rudisha's teammate who took bronze. "He told me he's going to run a word record today. He's the best."
At Wembley, the United States women's football team won its third consecutive Olympic gold, beating Japan 2-1 to avenge its defeat on penalty kicks to the same team at last year's World Cup.
The U.S. victory came in front of a crowd of 80,203, the largest ever to see a women's football game at the Olympics.
Americans had more to cheer about as Ashton Eaton won gold in the decathlon.
Bolt said he wanted to become a living legend, but IOC chief Jacques Rogge wasn't ready to bestow that title even after the 200 win.
"Let him participate in three, four games, and he can be a legend. Already he's an icon."
Earlier, Oscar "The Blade Runner" Pistorius and the South African relay team raised the drama stakes at the Olympic Stadium.
Pistorius, a double-amputee who runs with carbon-fiber blades, and his relay teammates were knocked out of the 4x400-meter relay following a collision during the race, then readmitted.
A jury of appeal said South Africa "had been severely damaged" in a collision between Ofentse Mogawane and Kenyan runner Vincent Kiilu, who cut across him too soon in the second section of the heat. The jury decided to give the extra ninth lane to South Africa — silver medallists at the last world championships — for Friday's final.
While other runners took off with their batons after the changeover, Pistorius glanced back to see the baton wasn't coming, and dejectedly walked off the track. It would have been his last appearance at the Olympics after failing to qualify for the 400-meter final as an individual runner.
The incident unfolded as London enjoyed the warmest day of the Olympics so far.
Bolt won both the 100 and 200 — in world record times — in Beijing four years ago and with the 100 gold already collected, he joined Carl Lewis as the only athlete to win the race at successive games.
Training partner Yohan Blake, who beat Bolt in both the 100 and 200 at the Jamaican trials, was second in the 200.
Manteo Mitchell kept going after he felt something pop in his left leg halfway through the opening lap in the 4x400-meter relay preliminaries, helping the Americans tie for first with the Bahamas. A few hours later, doctors told him he had a broken leg.
Women's boxing made its Olympic debut this year and flyweight Nicola Adams of Britain had the distinction of winning the first gold medal. She stunned world champion Ren Cancan of China 16-7, knocking Ren down in the second round with a dynamic flurry of punches.
Katie Taylor of Ireland won the lightweight gold medal, edging Sofya Ochigava of Russia 10-8. Taylor is the unofficial pound-for-pound champion of women's boxing after winning the past four world titles with an entertaining style.
U.S. middleweight Claressa Shields beat Nadezda Torlopova of Russia 19-12. The 17-year-old Shields shuffled, danced and slugged her way past her 33-year-old opponent with a charisma rarely seen in boxing. The teenager even got a telling-off from the referee for poking her tongue out at her opponent. As the bout ended she gave a distinctive shuffle and danced away from the ring after being declared winner.
Eva Risztov of Hungary won the women's open water race at Hyde Park, holding off American Haley Anderson in a sprint to the finish. Risztov was in front most of the way in the grueling 10-kilometre race, leading a five-woman pack that broke away from the rest of the field.
Martina Grimaldi of Italy took the bronze and world champion Keri-Anne Payne of Britain fourth, disappointing the huge British crowd that lined the banks of the Serpentine.
There was no home disappointment at Greenwich Park, where Charlotte Dujardin of Britain won the individual dressage gold medal on Valegro, scoring 90.089 per cent in the deciding grand prix musical freestyle which featured Olympic theme music and chimes from Big Ben.
Adelinde Cornelissen of the Netherlands, riding Parzival, won silver, while Laura Bechtolsheimer of Britain on Mistral Hojris took the bronze.
At Weymouth, the men's 470 medals race on the English Channel was postponed because of lack of wind. The race was rescheduled for Friday, when the women's 470 medals race will also be held.
The gold medal will go to either Mathew Belcher and Malcolm Page of Australia or Luke Patience and Stuart Bithell of Britain. The Australians have 18 points and the British 22.
In women's football, Canada beat France 1-0 for the bronze medal in Coventry. The Canadians then packed their bags to head to Wembley, 100 miles (160 kilometres) south, where they were to receive their medals during the gold medal match.
In doping news, an Olympic official familiar with the case said the IOC is set to formally strip American cyclist Tyler Hamilton of his gold from the 2004 Athens Games and reassign the medals after his admission of doping.
With the eight-year deadline approaching, the official told The Associated Press the IOC executive board will meet Friday to readjust the standings from the road race time trial. The official spoke on condition of anonymity because the decision hasn't been announced yet.
The gold will now go to retired Russian rider Viatcheslav Ekimov. American Bobby Julich will be moved up from bronze to silver, and Michael Rogers of Australia from fourth to bronze.
AP Sports Writer Stephen Wilson contributed to this report.