US sprinter Manteo Mitchell breaks his leg in 400m relay – but they still make the final

Athletes often speak of running through the pain barrier. But American Manteo Mitchell gave the phrase a whole new meaning yesterday when it emerged he stormed around the Olympic Stadium on a broken leg.

In an extraordinary act of placing mind over matter, the 25-year-old helped the United States to finish joint fastest qualifiers in the men's 4x400m relay heats despite hearing his left fibula bone snap halfway around the track. Mitchell continued with the baton on the opening leg of the relay and managed to hand it to his teammate Josh Mance in 45 seconds – only a second slower than his target time.

He said: "I got out pretty slow, but I picked it up and when I got to the 100m mark it felt weird. I was thinking I just didn't feel right. As soon as I took the first step past the 200m mark I felt it break. I heard it. I even put out a little war cry, but the crowd was so loud you couldn't hear it. I wanted to just lie down. It felt like somebody literally snapped my leg in half."

Mitchell said he was motivated to continue by the fear of letting down his teammates and the sight of Mance beckoning him on.

He said: "I knew if I finished strong we could still get it [the baton] around. I saw Josh Mance motioning me in for me to hand it off to him, which lifted me. I didn't want to let those three guys down, or the team down, so I just ran on it. It hurt so bad. I'm pretty amazed that I still split 45 seconds on a broken leg."

Mitchell, who helped ensure the US qualified in a dead heat of two minutes 58.87 seconds with the Bahamas, said he thought the injury was linked to an incident three days earlier when he missed some stairs in the Olympic Village and landed awkwardly.

An X-ray last night confirmed the break, meaning that he will play no part in tomorrow's 4x400m final.