With a jam-packed stadium crackling with anticipation, Bolt clocked 9.63 seconds 0.06 seconds faster than he ran in Beijing, an Olympic record and became the only man other than Carl Lewis in 1988 to defend the 100-meter title.
"It really means a lot, because there's a lot of people doubting me," Bolt said. "There's a lot of people saying I wasn't going to win, I didn't look good. There was a lot of talk. So for me, it was even greater feeling to come out here and defend my title and show the world that I'm still No. 1. I'm still the best."
Not just now, either.
Bolt now has four Olympic gold medals, with opportunities for two more yet to come in the 200 meters and the 4x100 relay. He owns the two fastest 100 times in Olympic history and the world record in both the 100 and 200 both set in Berlin in 2009 and just defeated the fastest field ever assembled.
Seven of the eight finalists ran 9.98 or faster. The third-, fourth- and fifth-place times were the fastest ever for those finishing positions. No other champion in history would even have won a medal here with their winning times from the past.
"I'm sorry," said Ato Boldon, the two-time Olympic medalist who's now an analyst for NBC. "Carl and Jesse [Owens] and ... everybody are behind Bolt now. Because not only did he defend, he defended against guys who are very much his equal.
"For me," he added, "this was the best race ever."
Fellow Jamaican Yohan Blake finished second in 9.75, with former Olympic champion Justin Gatlin of the United States in third in 9.79 after coming back from a four-year drug ban, beating countryman Tyson Gay by 0.01 seconds for the bronze medal.
"It's tough, but I have no excuses," Gay said, tears in his eyes. "I gave my all."
Gay was world champion five years ago, and owned the second-fastest time ever coming into the race. But he has never won an Olympic medal, with injuries ruining his effort four years ago and the supreme talent that is Bolt helping keep him off the podium this time.
Yet many viewed Bolt as vulnerable here, after he lost to Blake at both 100 and 200 meters in the Jamaican Olympic trials and strained against hamstring and back injuries recently. He had to pull out of a race in Monaco last month, and ran only the third-fastest time in the semifinals, behind Blake and Gatlin.
Once the starting gun fired, though, it was all Bolt.
Characteristically slow out of the blocks, the 6-foot-5 powerhouse quickly used his giant strides to churn past his rivals, powering past Gatlin about halfway home. He didn't slow down and celebrate before the finish this time, either, the way he did in Beijing, and instead flew through the line glancing over at his spectacular time.
"My coach explained to me after the trials that I should stop worrying about my starts," Bolt said. "So for me, it was all about just reacting and executing … because I know my last 50 meters is the best part of my race.
"I just ran, pretty much," he said.
And just like Beijing, he left everybody in awe. Even his rivals could not help but appreciate the legend sprinting ahead of them.
"He has superior talent," said Richard Thompson, the 2008 silver medalist from Trinidad and Tobago who finished seventh. "That's just something that, no matter how hard you train, there's nothing you can do to be born with the talent that he has."
Bolt said he wants to leave London a legend, and the 100 was part of the plan.
"That's a first step for me," he said, laughing and teasing through a post-race press conference. "I think after I defend my 200-meter title also, then I will consider myself a legend. So this is one step in the door."
An awfully fast one, at that.
Storylines Bolt topsa blazing field
R Usain Bolt of Jamaica clocked a time of 9.63 seconds, an Olympic record.
• Jamaica's Yohan Blake and the United States' Justin Gatlin were second and third, just ahead of American Tyson Gay.
• Seven of the eight finalists ran 9.98 or faster, making it the fastest field ever.