 Coleman's performances at under-21 level saw him supplant John Mitchell as second-choice goalkeeper with the Cork senior team shortly after the 1970 Munster Championship.He made his championship debut on 16 August 1970 as a replacement for the injured Paddy Barry in Cork's 4-20 to 2-09 All-Ireland semi-final defeat of Antrim.Coleman was later included as a panellist for the All-Ireland final against Wexford and ended the game with a winners' medal after the 6-20 to 5-11 victory.