Athletics World Championships 2011
- Venue: Daegu, South Korea
- Date: 27 August - 4 September
Coverage: Listen live on BBC Radio 5 live, 5 live sports extra and online (UK only), watch daily video highlights on the BBC Sport website (UK only); live text commentary on the finals; watch live on Channel 4
Chambers' twitch on the blocks was enough for instant disqualification
Britain's Dwain Chambers is out of the 100m at the World Athletics Championships after being disqualified for a false start in his semi-final.
Chambers is the second Briton to suffer disqualification at the Championships in Daegu after Christine Ohuruogu's exit in the 400m on Saturday.
Chambers told BBC Radio 5 Live he had no complaints about the decision.
"The gun went and I moved before it fired. It was unfortunate, but it was enough. Rules are rules," he said.
Chambers was penalised in the first of three semi-finals as he looked to come through a tough heat featuring Jamaica's Yohan Blake and American Walter Dix.
Only the first two qualified automatically for the final and Chambers, mindful of the need to make a blistering start, twitched in the starting blocks and triggered the false start.
Chambers added: "This is what we have to learn to cope with, I knew I had to run beyond my best to qualify for the final but ended up false-starting. I have a team here to support and when I get home I will consider my situation."
Former Olympian and BBC Radio 5 Live summariser
“For Dwain to be disqualified for the movement of his foot, it's harsh, but those are the rules - one false start means you are out. He only moved his foot ever so slightly, but those pads on the blocks pick up any movement and potentially this could be the last time we see Dwain in a major race.”
The two other British athletes, Harry Aikines-Aryeetey and Marlon Devonish, also failed to progress into the final.
Aikines-Aryeetey edged out former Olympic champion Justin Gatlin to take third in his semi-final but it was not enough to make the last eight.
Devonish, 35, finished seventh in the same heat as reigning world and Olympic champion Usain Bolt, who cruised to victory in 10.05 seconds.
Devonish told BBC Radio 5 Live: "Dwain is a pedigree athlete but it's so difficult to maintain your composure, it's very noisy in here, noisier than you think, and trying to maintain your focus is hard, you respond to the noise in the crowd.
"I feel for him because to go out to a false start is harsh. That's two Brits now and it's a nightmare."