British sprint duo into semis

Dwain Chambers and Tyrone Edgar advanced to the semi-finals of the men's 100m at the World Championships in Berlin but British number one Simeon Williamson crashed out.

Chambers clocked 10.04 seconds, a season's best, in winning his heat, Edgar was second in 10.12 in his, but Williamson was only fifth in the final heat won by Daniel Bailey ahead of a cruising Usain Bolt.

Former world record holder Asafa Powell set the fastest time with 9.95 ahead of defending champion Tyson Gay who clocked 9.98.

"I've worked well this summer so I have to do the best I can, which is to keep on qualifying," Chambers said.

"Once I'm in the final, which I'm confident of doing, then anything can happen. I'm glad I was able to get through today, my mind was all over the place this morning, I felt tight."

Asked about his season's best, Chambers added: "I can't complain as long as each round I get better and better, that's the most I can do.

"When I get into a championship I can't worry about what's happened in the past, I just have to get on with what's going on now and concentrate on the running, it's the best I can do."

A hugely disappointed Williamson, who had beaten Chambers impressively in the trials last month, said: "I got cramp after the third step in both legs.

"They just went 'bang, bang'. I didn't feel anything when I was warming up but I will be okay for the relay."