LONDON -- In his first appearance at the London Olympics, Usain Bolt did what he had to do to advance to the 100-meter semifinals, overcoming a slow start to win his heat in 10.09 seconds Saturday.

Bolt dominated the Beijing Games four years ago, winning golds in world-record times in the 100, 200 and 4x100 relay - something no man had ever done at an Olympics. At the 2009 world championships, he lowered his 100 mark to 9.58, which still stands.But he's been less than outstanding more recently. A false start knocked him out of the dash at last year's world championships, and he lost to training partner Yohan Blake in the 100 and 200 at the Jamaican Olympic trials. Bolt blamed his poor showings at home on back and hamstring issues.

"My legs are great. My training has been great," Bolt said Saturday. "I'm feeling better."

Might very well be true. Still, his reaction time was only sixth-best in his eight-man heat - the sort of slow start that could make things tough Sunday night, when the 100 semifinals and final are scheduled.

"I stumbled on the start," Bolt said. "I really didn't do a lot of executing."

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  • Jamaica's Usain Bolt, left, crosses the finish line ahead of Ryan Bailey of the United States in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt, left, heads for the finish line ahead of Ryan Bailey of the United States in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt, right, and United States' Ryan Bailey run the final leg of the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/Matt Dunham)

  • Jamaica's Usain Bolt and Great Britain's Mohamed Farah imitate each other after the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt poses on the podium after receiving his gold medal for the men's 4x100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/Matt Dunham)

  • United States' Ryan Bailey, left, and Jamaica's Usain Bolt, second from right, power ahead after receiving the batons from their team members in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Matt Dunham)

  • United States' Ryan Bailey, left, receives the baton from United States' Tyson Gay, second from left, as Jamaica's Usain Bolt, second from right, receives the baton from Jamaica's Yohan Blake in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Matt Dunham)

  • Jamaica's Nesta Carter, Michael Frater, Usain Bolt and Yohan Blake celebrate as they receive their gold medals for the men's 4x100-meter during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt, right, and Yohan Blake celebrate their win in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt, right, and Yohan Blake celebrate their win in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt takes the baton to lead in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Daniel Ochoa De Olza)

  • Jamaica's Yohan Blake, Usain Bolt, Nesta Carter, and Michael Frater pose with their national flag after their gold medal win in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds.(AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt prepares to pass United States' Ryan Bailey in the men's 4 x 100-meter relay during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. Jamaica set a new world record with a time of 36.84 seconds. (AP Photo/Martin Meissner)

  • Jamaica's Usain Bolt, right, and Jamaica's Yohan Blake celebrate winning gold and setting a new world record with a time of 36.84 seconds in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt, right, and Jamaica's Yohan Blake celebrate winning gold and setting a new world record with a time of 36.84 seconds in the men's 4x100-meter relay final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Saturday, Aug. 11, 2012. (AP Photo/Matt Dunham)

  • Jamaica's Usain Bolt celebrates winning the gold medal in front of the Olympic flame after the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt, right, is surrounded by photographers after winning gold in the men's 200-meter during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Lee Jin-man)

  • Jamaica's Usain Bolt celebrates winning the gold medal in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Lee Jin-man)

  • Jamaica's Usain Bolt celebrates his gold medal win in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt kisses the track after winning the gold medal in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Lee Jin-man)

  • Jamaica's Usain Bolt, center, is embraced by his mother Jennifer, center left, after he won gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt celebrates his gold medal win in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt, left, hugs his teammate Yohan Blake after winning the gold medal in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Lee Jin-man)

  • Jamaica's Usain Bolt races to his gold medal finish in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Gregory Bull)

  • Jamaica's Usain Bolt, center, runs to win gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. Others runners are, from left, South Africa's Anaso Jobodwana, Jamaica's Warren Weir and United States' Wallace Spearmon. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt celebrates his gold medal win in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt runs to win gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt strikes his signature pose after his gold medal win in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt runs to win gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt runs to win gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Matt Slocum)

  • Jamaica's Usain Bolt, right, celebrates winning gold in the men's 200-meter final with spectators during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt celebrates winning gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt does a press up on the track after winning the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Christophe Ena)

  • Jamaica's Usain Bolt, center, Jamaica's Yohan Blake, left, and Jamaica's Warren Weir celebrate their medals in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. Bolt won gold, Blake silver and Weir bronze. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt reacts as he wins the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Christophe Ena)

  • Jamaica's Usain Bolt celebrates as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Martin Meissner)

  • Jamaica's Yohan Blake, left, celebrates winning silver with Jamaica's Usain Bolt, who won gold, following the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt, left, gestures after crossing the finish line to win gold ahead of silver medallist Yohan Blake of Jamaica, center, and bronze medallist Warren Weir of Jamaica in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt, third left, reacts as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Martin Meissner)

  • Jamaica's Usain Bolt second left, reacts as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt wins the finals of the men's 200-meter in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Morry Gash)

  • Jamaica's Usain Bolt reacts as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Lee Jin-man)

  • Jamaica's Usain Bolt celebrates as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt gestures as he crosses the finish line to win gold in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/David J. Phillip)

  • Jamaica's Usain Bolt gestures as he wins the finals of the men's 200-meter in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Morry Gash)

  • Jamaica's Usain Bolt celebrates as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt celebrates as he crosses the finish line to win the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Anja Niedringhaus)

  • Jamaica's Usain Bolt, foreground, crosses the finish line to win gold ahead of Jamaica's Yohan Blake in the men's 200-meter final during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Matt Dunham)

  • Jamaica's Usain Bolt crosses the finish line to win the gold medal in the men's 200-meter final during the athletics in the Olympic Park during the 2012 Summer Olympics, Thursday, Aug. 9, 2012, in London. (AP Photo/Mark Baker)

  • Jamaica's Usain Bolt gestures as he wins the finals of the men's 200-meter in the Olympic Stadium at the 2012 Summer Olympics, London, Thursday, Aug. 9, 2012. (AP Photo/Morry Gash)


Blake, whose intensity in practice led Bolt to nickname him "The Beast," looked quite good in his Olympic debut, really coasting at the end while winning his heat in 10 seconds flat.

Asked to assess his showing, Blake said: "It's not the finals."

If Saturday is any indication of what's to come with medals at stake, fans could be in for a treat.

All five top contenders won their opening heats, as expected: Tyson Gay, Asafa Powell and 2004 Olympic champion Justin Gatlin, in addition to Bolt and Blake. It's worth noting that Bolt was the least impressive of any. Then again, he didn't really have an opponent to threaten him even the least bit in Heat 4; none of the other entrants ever has run 9.9 or better.

If Gay was looking for a solid test of his surgically repaired right hip, he got it. Pushed by Richard Thompson of Trinidad and Tobago, who left Beijing with two silver medals, Gay got no chance to really let up while winning Heat 1 in 10.08. Thompson was next in 10.14.

Afterward, Gay leaned over, hands on his knees, and watched a replay of his race on the stadium scoreboard.

"Start felt good. Everything felt pretty good," Gay said. "I didn't feel any pain. ... I really didn't want to run (any) faster. I did what I wanted to do."

Moments later, it was Gatlin's turn to push it, and he did - except not because anyone was anywhere near him but because he could. Gatlin opened a large lead and only let up in the final few strides, glancing to his left to eye the 9.97 on the trackside clock - a full quarter of a second faster than runner-up Derrick Adkins of the Bahamas.

The stadium announcer noted that Gatlin's time was the fastest first-round 100 in Olympic history.

That distinction didn't last long.

In the very next heat, Ryan Bailey of the U.S. went even faster, finishing in 9.88, matching his personal best. This was, after all, Bailey's chance to get his name in lights. He didn't necessarily come here with realistic hopes of going home with the gold, the way, say, Blake did.

Bailey sought out a TV in the bowels of the stadium to see Bolt in the next heat.

"He's the equivalent of the guy walking on the moon for the first time. He's done something that no one has ever done before. You have to line up in the blocks, shoulder-to-shoulder, with this guy? You're going to be in awe sometimes," Gatlin said about Bolt. "I think a lot of runners almost have that audience mentality: See what he's going to do, even while you're running. You've got to block that out, go out there and compete against that guy."

Gatlin, Gay, Powell and Blake will aim to do just that on Sunday.

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