Career
O'Sullivan joined the team as substitute goalkeeper during the 1963 championship, and took over as first-choice goalkeeper at the end of the decade. He retained that position until his retirement after the 1972 championship. At club level O'Sullivan enjoyed a lengthy career with Cashel King Cormacs GAA.
Club
O'Sullivan played his club hurling with his local Cashel club.
Inter-county
Tipp subsequently lined out against Kilkenny in the All-Ireland minor decider. A high-scoring game developed over the hour, however, O'Sullivan let in three goals and Kilkenny emerged victorious by 3-13 to 0-15. O'Sullivan later joined the county under-21 team.
An All-Ireland final appearance beckoned, with Wexford providing the opposition. The victory gave O'Sullivan's a coveted All-Ireland under-21 winners' medal. O'Sullivan subsequently joined the Tipperary senior inter-county team, making his debut as a substitute in the Munster final defeat by Cork in 1970.
He became the first-choice goalkeeper on the team in 1971 and it proved to be a successful year. That year he started in his first full Munster final against Limerick. An exciting game developed, however, at the full-time whistle Tipp were the 4-16 to 3-18 winners.
Kilkenny provided the opposition against Tipperary in the subsequent All-Ireland final, the first to be broadcast in colour by Telfis Éireann. In an exciting and high-scoring game Tipp relied on two freak goals to capture a 5-17 to 5-14 victory. The game itself is still remembered for the image of Babs Keating discarding his worn-out boots and playing the last few minutes of the match in his bare feet.
The victory gave O'Sullivan a coveted senior All-Ireland winners' medal in the senior grade. Tipperary quickly surrendered their Munster and All-Ireland titles in 1972, and O'Sullivan was replaced as goalkeeper in 1973. Inter-provincial
O'Sullivan also lined out with Munster in the inter-provincial hurling championship.
