MOSCOW -- Usain Bolt's pre-race antics were rather subdued. Very little emotion, not much enthusiasm -- at least not by his usually fun-loving standards.

His race was pretty ho-hum, too, just a quick burst out of the starting blocks before backing off and coasting across the finish line.

Sure, the Jamaican easily won his opening heat of the 100 metres Saturday at the world championships. But the only thing dashing about Bolt on this humid night was his tiger-striped uniform.

The crowd really wasn't into the action, either, with a half-full audience giving Bolt & Co. a tepid applause at best.

But there was some drama, with the gun quickly sounding again soon after the runners flew off the line. A hush fell over the stadium as someone was about to be disqualified for jumping the gun.

This time, it wasn't Bolt. This time, it was a lane over from him. Still, the situation was eerily reminiscent of when Bolt was disqualified in the 2011 final at the worlds.

"I wasn't really worried," said Bolt, who was seventh overall. "It was a good run. Just all about getting through to the next round. Took it easy and got it done."

So did Mike Rodgers, who turned in the top 100 time at 9.98 seconds -- nearly a full tenth of a second faster than Bolt, which is a landslide in track. Justin Gatlin, the sprinter who's supposed to give Bolt the biggest challenge in the final on Sunday, won his heat, too, in 9.99.

The biggest buzz from the audience all night was when the fans were swaying to the reggae beats of Bob Marley's classic "Three Little Birds," with the lyrics "Don't worry, 'bout a thing. 'Cause every little thing is gonna be all right."'

These days, everything in track is far from all right.

Recent doping scandals have left a stain on the sport. Missing from these championships are big names such as Tyson Gay, Asafa Powell, Veronica Campbell-Brown and Sherone Simpson, all following positive tests for banned substances.

Bolt could be just the person to make fans forget about those transgressions and put the focus back on track.

"Usain brings that ray of light to the sport," said Dwain Chambers, a British sprinter who once served a doping suspension and advanced to Sunday's semifinals. "People enjoy watching him. He's exciting to watch."

Closely tracking Bolt's performance on a television monitor inside the stadium was Gatlin, possibly the only one capable of beating Bolt at the worlds. Especially with Gay, Bolt's biggest rival, out, and defending champion Yohan Blake, Bolt's teammate, sidelined with an injured hamstring.

Gatlin beat Bolt in Rome two months ago and is eager to show that it was no fluke and that he's catching up to the world-record holder.

"Bolt ran easy," Gatlin said. "He's not the Bolt from 2012, but I think he's going to come out here and do a really good job.

"I think we're going to go out there and make some electricity happen."

Gay's spot in the field went to Rodgers and he ran with the chance. Rodgers has long been the future of American sprinting, but hasn't been able to stay healthy. He also missed the 2011 world championships after testing positive for a banned stimulant, which earned him a suspension.

"I feel pretty good," Rodgers said of his race. "I feel like I'm in the best shape of my life."

Overlooked, too, with Bolt and Gatlin receiving most of the attention.

"That's the party I'm coming to crash," Rodgers said. "Nobody saw my race in London (last month), when I was beating Bolt for 70 metres."

But this is the 100 metres and nobody covers that much ground better than Bolt. Especially when he's motivated.

"This is the quarterfinals. I wasn't really worried," Bolt said. "I'm feeling good."