Kirby first came to prominence on the inter-county scene as a member of the Limerick minor hurling team in the early 1980s. After losing nine provincial deciders since their last success in 1965, Kirby's minor team went into the 1984 unster final as underdogs. Tipperary, the team that had beaten Limerick in the two previous deciders, provided the opposition once again. At the long whistle Limerick were the champions by 3-6 to 2-7 and Kirby collected a Munster minor winners' medal. Limerick later qualified for the All-Ireland final with Kilkenny providing the opposition. It was the very first meeting between these two sides in the minor championship. An exciting game developed, however, at the full-time whistle both sides were level and a replay was required. The second encounter between the two sides was a low-scoring tense affair; however, Limerick narrowly triumphed by 2-5 to 2-4 and Kirby collected an All-Ireland minor winners' medal.