Ireland's David Gillick crossed the line in fifth place in the final of the 400m at the World Indoor Championships in Doha, but was subsequently disqualified after clashing with the American Bershawn Jackson, with 200 metres to go.
Gillick had a solid start from the unfavourable lane three and was in fourth place going into the second lap, but momentum was lost after the incident with Jackson.
He regained his stride but with only 40 metres left in the race it was too late and the athletes behind him, who now had the momentum, passed him.
Christopher Brown from the Bahamas streaked ahead to take the gold medal in 45.96s, with Cuba's William Collazo claiming silver and American Jamaal Torrance bronze.
Speaking after the race Gillick said: 'I am bitterly, bitterly disappointed as I really wanted a medal.'
An attempt was made by the Irish team to counter appeal Gillick's disqualification but they were told that the jurys decision is final.
