Britain's Robert Newton and Andy Turner missed out on qualification for the second round of the 110m hurdles heats on Tuesday.
Turner was last in his heat in 13.75 seconds
Newton was seventh in his heat in 13.85 seconds, while Turner clocked 13.75 with the first four from each heat plus the eight fastest losers progressing.
France's Ladji Doucoure was fastest overall in 13.18.
Defending champion Anier Garcia of Cuba won his heat in 13.24, with world champion Allen Johnson also through.
Newton was unhappy with his performance and immediately left the stadium but Turner revealed that he had torn a leg muscle at the team's holding camp
"The first part of the race was okay but then it just went to pieces and I
don't really know what happened, I am a bit annoyed," said Turner.
"I have had only two or three quality training sessions since getting injured
in Cyprus, although the training has been fine."
Sydney silver medallist American Terrence Trammell stumbled through to the second round as a fastest loser, finishing fifth in his heat in 13.51 seconds.
"It did not go too well," the 25-year-old Trammell said.
"I was a bit sluggish out there. I do not want to
make any excuses but we all had to wake up at 5 a.m. this
morning and I was not able to get a whole lot of sprinting in
before the heat."
Johnson, the champion in Atlanta in 1996, said: "It felt great, I'm happy I advanced.
"Everyone is running fast so it needs big