Born in Milltown in 1917 but living for many years in nearby Ballymore, Sean played football for Milltown along with his brothers Padraig and Conor. They were part of the 1936 junior championship winning team, while Sean was corner forward on the team that claimed senior championship honours two years later.

He was also part of the side that won senior championship, Feis Cup and league titles in 1942. The club was forced to disband a few years later due to a lack of players, but Sean was later instrumental in reviving it.