Jack Green has claimed that his exit in the 400m hurdles was a "complete waste of time" after falling in the semi-final.
The British athelete was expected to be in contention to make the final but a mistake in the first half of the race spelled the end of his Olympics.
Green told BBC Sport: "I just got too close to the hurdle. It was one of those things. I went for it but I think I went to hard.
"I went for it but I think I went to hard. It was a stupid fall and a complete waste of time. I far too angry for anything to hurt right now."
Green's teammate Dai Greene has qualified for the final as a fastest loser.