O'Reilly joined the Kilmallock club at a young age and played in all grades at juvenile and underage levels, before joining the club's senior team.
Inter-county
Minor and under-21
O'Reilly first played for Limerick at minor level. On 2 July 2015, he made his first appearance for the team when he came on as a late substitute in Limerick's 1-14 to 0-14 Munster Championship defeat of Cork.[1]
O'Reilly subsequently joined the Limerick under-21 hurling team in 2016 and played during the team's unsuccessful championship campaign.[2] He was included on the panel again the following season and won a Munster Championship medal after a 0-16 to 1-11 defeat of Cork in the final.[3] On 9 September 2017, he came on as a substitute for Barry Murphy in Limerick's 0-17 to 0-11 defeat of Kilkenny in the All-Ireland final.[4]
Under-25
In 2017, O'Reilly joined the Limerick under-25 hurling team. On 18 June 2017, he scored 3-01 from play when Limerick defeated Waterford by 4-12 to 1-19 to win the Munster Championship.[5]
Senior
O'Reilly joined the Limerick senior hurling panel in 2018 and made his first appearance for the team during the pre-season Munster League.[6][7] He made his first appearance in the National Hurling League on 4 February 2018 in a 1-24 to 0-10 defeat of Offaly at O'Connor Park.[8] On 19 August 2018, O'Reilly was a member of the extended panel when Limerick won their first All-Ireland title in 45 years after a 3-16 to 2-18 defeat of Galway in the final.[9]
O'Reilly was a member of Limerick's extended panel once again during the 2019 National League, however, he made no appearance during Limerick's eight-game run to the title.[10] He was dropped from the panel prior to the start of the Munster Championship.[11]