O'Connor joined the Sarsfields club at a young age and played in all grades at juvenile and underage levels, winning a premier under-21 championship medal in 2017 following an eight-point defeat of Killeagh-St Ita's.
[1] O'Connor first played for Cork at minor level in 2016, however, his sole season in the grade ended with a defeat by Tipperary in the Munster semi-final.
[3] On 4 July 2018, O'Connor won a Munster medal after scoring 1-02 from play in Cork's 2–23 to 1–13 defeat of Tipperary in the final.
[4] On 26 August 2018, he scored a point from play in Cork's 3–13 to 1-16 All-Ireland final defeat by Tipperary in what was his last game in the grade.
[5] O'Connor made his senior debut for Cork on 27 January 2018, replacing Alan Cadogan for the final nine minutes of a National League game against Kilkenny at Páirc Uí Chaoimh.