*Club domestic league appearances and goals, correct as of 08:38, 16 September 2024 (UTC) ‡ National team caps and goals, correct as of 13:03, 9 September 2024 (UTC)
Upon returning to Crewe, he made his Crewe debut on 1 December 2021, being named in the starting line-up for an EFL Trophy knock-out game against Doncaster Rovers at Gresty Road.[5] Still an Academy scholar, he made his first league start on 29 January 2022 at Gresty Road against Rotherham United.[6] He signed his first professional deal with the club at the end of the 2021–22 season.[7]
In his third game following his January 2023 return to Crewe, O'Riordan scored his first professional goal, in a 1–1 League Two draw with Stockport County on 31 January.[10] On 25 February 2023, he received his first career red card, being sent off after a second caution in the 87th minute of Crewe's 1–1 draw with Rochdale.[11] After suspension, he scored his second Crewe goal in his next game, a 4–3 win over Salford City at Gresty Road on 10 March 2023.[12]
Blackburn Rovers
On 24 January 2024, O'Riordan joined Blackburn Rovers on a four-and-a-half-year deal,[13] for an undisclosed fee.[14] He made his Blackburn debut as a 68th minute substitute in the side's 3–1 win over Stoke City on 10 February 2024.[15]
On 12 August 2024, O'Riordan joined Cambridge United on loan for the 2024/25 season.[16]
On 2 October 2023, in an apparent switch of allegiance, Scot Gemmill named O'Riordan in the Scotland U21 squad,[17] but two days later the defender pulled out to represent Ireland instead,[21][22] and on 5 October was named in the country's U21 squad to play Latvia,[23] gaining a second U21 cap in Ireland's 2–1 victory on 14 October 2023.[24]
