``I knew it was going to be like this. There wasn't a doubt in my mind it was going to be like this,'' Bolt said after setting an Olympic record of 9.63 seconds, just .05 of a second outside his world mark.

World champion Blake equaled his personal best with 9.75 and Gatlin took bronze in 9.79.

Unlike his showboating and coasting during a then world-record run at Beijing four years ago, Bolt was all business until near the finish on Sunday night, even leaning at the line. That proved how seriously he took the challenge of his younger training partner, Blake.

Bolt ran on, then knelt and leaned his head downwards, kissing the track before standing and assuming his trademark ``To The World'' pose _ pointing both fingers in the air for the first time during the Olympics. The crowd roared and later responded with chants of ``Usain, Usain.''

Blake celebrated with Bolt, the pair embracing in front of Jamaican fans in the jam-packed 80,000-seat stadium.

Bolt has been troubled by a stuttering start since he was disqualified for a false start in the final of last year's world championship, which brought Blake to the fore. In London, he proved that even with a slower kick out of the blocks, he still is in a class of his own.

``I executed and that's the key. I stopped worrying about the start. The end is what's important,'' Bolt said.

``My coach told me to stop worrying about the start and concentrate on the end, because that's my best.''

He left nobody in any doubt about that.

``The entire world says he's unbeatable and right now he is,'' said Richard Thomson of Trinidad and Tobago, who finished seventh in the final. The first seven finishers all had sub-10-second times. Asafa Powell was injured and finished well off the pace in eighth.

But the 1-2 finish by his Jamaican teammates further confirmed the domination of the Caribbean nation of 2.9 million in its sprint rivalry with the United States.

One day earlier, Shelly-Ann Fraser-Pryce had also defended her Olympic title in the women's 100, with Carmelita Jeter the lone American on the podium.

The United States did get its first gold of the athletics program at London when Sanya Richards-Ross held off a late charge of Britain's Christine Ohuruogu to win the women's 400.

One day after making his Olympic debut, double-amputee runner Oscar Pistorius failed to reach the final of the 400 meters, following a bad start with a slow race to finish last in his semifinal heat.

The first amputee to compete in track at the Olympics never stood a chance and finished the race on his fiber carbon blades in 46.54 seconds, .95 of a second behind winner Kirani James of Grenada.

Still, world champion James immediately walked over to Pistorius after the race and asked for his bib as a souvenir.

``It is an honor to compete against the guy,'' James said. ``Just coming out here to the Olympics and to compete, is very special for us.''

Pistorius is still expected to run the 4x400 relays, which start Thursday. Last year, Pistorius and South Africa won the silver at the world championships.

The sprinters were racing under partly cloudy evening skies, only hours after the women's Olympic marathon set off and finished in pouring rain. And, as unpredictable as the British weather, Ethiopia's Tika Gelana upset the favored Kenyans in the marathon.

It was the second long-distance battle the Ethiopians won over the Kenyans at the games. And just as Tirunesh Dibaba made her finishing kick count in the 10,000-meters on the track, Gelana left it until late to kick for the line.

With clenched teeth she sprinted along the glistening Mall to finish in 2 hours, 23 minutes and seven seconds, an Olympic record, leaving Priscah Jeptoo of Kenya with silver. Russian former steeplechaser Tatyana Petrova Arkhipova was the surprise bronze medalist.

Kenya did collect its first gold in the track program when Ezekiel Kemboi won the 3,000-meter steeplechase Sunday night, eight years after winning at the Athens Olympics.

European champion Mahiedine Mekhissi-Benabbad of France took silver and African champion Abel Mutai of Kenya took bronze. (AP)