Two years later Kirby was a key member of the Limerick under-21 hurling team. A Munster final appearance beckoned with near neighbours Clare providing the opposition. A close game developed and, at the end, both sides were level with 3-9 apiece. The subsequent replay was something akin to a walkover for Limerick. A 2-10 to 0-3 score line gave Limerick the win and gave Kirby a Munster winners' medal in the under-21 grade. Limerick, however, were later beaten in the All-Ireland semi-final.