O Colmain, who was affectionately known as Gerry Coleman, though he preferred the Irish version of his name, won the European amateur heavyweight championship at the National Stadium in 1947 and a record seven national senior heavyweight titles between 1946 and 1952.
O Colmain was also national senior light-heavyweight champion in 1943 and 1944, and represented Ireland in the 1948 Olympic Games in London.
He had around 200 contests in a 13-year career, losing about 20. He turned down several offers to go professional.
May he rest in peace.
