 O'Neill was called up for a trial with the Limerick minor team prior to the start of the 1991 season, however, he failed to make the championship panel.Again eligible for the grade the following year, he was an unused substitute on 22 April 1992 when Limerick suffered a 1-07 to 0-09 defeat by Tipperary in the Munster Championship.On 16 April 1993, O'Neill made his first appearance for the Limerick under-21 team.