If you were looking for clues to who might win the most open World Championship 100m in years, a meeting in a Paris hotel on Thursday would have told you a great deal.

On a brightly-lit stage sat Maurice Greene, three-time world 100m gold medallist and reigning Olympic champion, and Dwain Chambers, European champion and Britain's big hope at these Worlds.

They were there to tell the world's media about their sponsor's new running shoe. No-one cared about that.

This was all about 10 seconds of flat-out sprinting in the Stade de France. Like heavyweight boxers before a world title fight, the pair were fired up and ready to talk.

The big difference was that, this time around, the script had been changed.

For most of the past six years, Greene has been the man to beat. From the moment he took his first world title in Athens in 1997, he maintained an air of absolute dominance at the major championships.

Not any more. Where once his pre-race talk rang with unshakeable confidence, now there is more than a hint of bluster.

He still walks with his old rolling swagger. He's still coming out with the same words. It's just that they don't sound as believable as they used to.

"I'm not satisfied with second place. I've come here for the gold medal," he says, only to suffer the indignity of a journalist asking him how he feels when people say he isn't the sprinter he once was.

"I'm laughing," he says, without a trace of a smile.

"I don't think anyone is the same athlete they were in 2001. Every champion changes from year to year. All that matters is to come out here and win the gold medal - period.

"I see myself going out there and winning it - that's how I'm going out there."

Chambers, by contrast, is a man growing into his role as one of the world's very best sprinters.

In years gone by he admitted being so intimidated by Greene that he went to his blocks a beaten man. These days it's Chambers doing the intimidating.

Seated next to Greene with the world's media throwing questions at him from every angle, he's as relaxed as a man lying on a beach.

"The key is to have fun and not take it too seriously," he says. "It's a serious job, but if you get too far with that, you get negative elements coming on board. You end up getting impatient and anxious.

"You can't worry about your opponents. They've all been out there before, so they know how to compete.

"Maurice is the one who's been dictating the pace for the past five years. He's had it all his own way, but the last year's been an opportunity for a few of us to gain some wins over him.

"We're on a level playing-field now, and it's going to be interesting to see which one of us is the toughest.

"When it comes to the crunch and your neck is on the line, that's when crazy things happen, that's when athletes are really tested to their full ability."

There's another problem for Greene. When he steps on the track for the heats of the 100m on Sunday, he won't have run an individual 100m race for 44 days.

That's a hell of a long time for an athlete supposedly fine-tuning for the biggest competition of the year.

"I've been training, I just haven't competed," Greene insists. "Me and my coach and my manager have a game plan, and we figured, sit back - we don't have to race."

It's an interesting notion. It might even be true. So might the rumour that Greene has barely run at the big meets this summer because the promoters refused to pay the substantial appearance fees he was asking for.

Just don't expect Greene to admit it. If he is down, he's still dangerous. His era of dominance might have gone, but in a one-off final he will always have a shot.

"It doesn't matter how many meets you run, or what you do - it all comes down to performing here," he says.

"I don't hide from anybody. My plan was preparation, and this is what I've prepared myself for. Nothing else matters to me.

"Some people might say I'm the favourite, some people might not. That doesn't concern me. All that concerns me is coming out of here with a gold medal.

I don't plan to lose. I want to do better than I've done before. To go where no man has gone before!

"I like doing impressive things that people say can't be done. I like to prove people wrong.

"I've always said that the more people that are watching, the better I perform. And there's going to be a lot of people watching this one, so I'm going to pull out some of my best performances."