By Ian Gordon, PA Sport, Edmonton

Maurice Greene scorched to a third successive 100 metres title at the World Championships in Edmonton tonight.

The Olympic champion clocked 9.82 secs with fellow Americans Tim Montgomery second in 9.85 and Bernard Williams third in 9.94.

Britain's Dwain Chambers was fifth in 9.99 with team-mate Christian Malcolm seventh in 10.11.

Greene's time was the fastest in the world this year and was just 0.03secs off his own world record.

But it was mighty close at the end as the Kansas Kannonball was challenged by Montgomery and Greene's knee gave way just before the finish line.

The 27-year-old hobbled off on his victory lap after becoming the first man since Carl Lewis to win the coveted world sprint title three times in succession.

The tension in the Commonwealth Stadium, barely half-full to its 40,000 capacity despite the importance of the race, built up after three false starts.

Chambers, bronze medallist at the last worlds in Seville two years ago, never looked like repeating that feat after a slow start.

But the 23-year-old Londoner still clocked 9.99secs - just 0.02 off his personal record.

Chambers was one of five men to finish under the 10secs barrier - one off the six sub 10s recorded in the 1991 final in Tokyo.

Malcolm, who lowered his Welsh record to 10.09 secs in the second round, was also never a medal challenger but can now look towards his main event - the 200m - in which Chambers is also competing.

Chambers, who had drawn the outside lane, said: ``It was always going to be difficult from lane eight. I wanted to be closer to Maurice and confidence wise I was a bit down when I heard the draw.

``All the action takes place in lanes three, four and five so all I could do was just run and hope I could nip in.

``But out there I couldn't see anything and I didn't know what had happened until after I crossed the line.

``If I had been in lane three or four then I think maybe things would have been different and the positions may have been different.

``But I am not upset in the slightest and I cannot complain. I gave it my best shot and I am pleased considering what I have been through this season in terms of injury and the bike accident. It hasn't been an easy year.

``I wish I could party tonight but I can't. It's a case of resting before the 200 metres and I am tired.''

Greene's knee had been the subject of speculation leading into the championships and he stated later: "No one is just going to give you the gold medal. You have to come out here and fight for it - and be willing to actually die for it.

"I'm just thankful for finishing the race the way I did and that I was able to pull it out. We had eight fast guys out there and everyone is coming for one thing - the gold medal."

Thrilled to have achieved a third victory ranking him alongside Carl Lewis, Greene added: "I'm not going to let them break it. They're going to have to take it."

The injury means Greene will not now defend the 200m title he won two years ago in Seville. But he will consider anchoring the US 4x100m relay team next weekend if fit.

"I felt something in my quad, then I took another step and I felt something in my hamstring in the last 10-15 metres of the race," he said. "I am not running the 200m. I don't know if I'm going to run the relay.

"If I'm 100%, I will run but I'm not going to jeopardise the United States relay team with my ego going out there if I'm not 100% fit.

Silver-medallist Montgomery, who was responsible for one of the false starts, admitted: "You cannot give a champion like Maurice anything at the start. And with the false start I gave him too much.

"I know I was on world record pace because you don't run a 9.82sec if you're not. With a start like I had I ran 9.85sec. He just posted 9.82sec - so it's my job to get out there and beat that time."

Claiming he was catching Greene at the end, Montgomery said his false start had stifled his performance.

He concluded: "After the start I looked and Maurice Greene was out there. And I was like 'I must get him'. I just ran out of the room. I know I have 9.75sec in my heart.

"I came out here to put it all on the line - and Maurice Greene proved to me why he's champion!"