Nicknamed The Derry Destroyer, he was a former IBA World and WBC Continental Americas Middleweight title holder.
He won 100 of 130 fights as an amateur, and won an Irish national title at age 15.
He won via knockout 18 times, with 10 of those knockouts occurring in the first round.
His uncle Jackie Duddy was killed by British Army Paratroopers, during Bloody Sunday.
His final fight was a loss against Julio Cesar Chavez Jr. on June 26, 2010.