O’Riordan first came to prominence with the Cork senior hurlers in the mid 1940s. He first tasted success in 1946 when he captured his first Munster title. This was later converted into a first All-Ireland medal following a victory over Kilkenny in the championship decider. The following year O’Riordan won a second Munster title, however, on this occasion Cork were defeated by Kilkenny in the All-Ireland final. O’Riordan won a third provincial medal in 1952, before later collecting his second and final All-Ireland medal following a victory over Dublin in the final.
Though he was more than six feet tall, Mossy was a hurling stylist with a powerful stroke. In the Minster semifinal of 1949 he struck a shot so hard that it rebounded of the the stanchion that in those days supported the netting behind the goals and the sliothar rebounded so quickly that the referee and his umpires assumed that it had rebounded off the crossbar. Mossy would say to the day he died that 'it was in' and GAA officialdom clearly concurred because Mossy's 'goal that never was' resulted in the GAA deciding to remove the offending stanchion and allowing the net to lie unsupported - as it is today. Incidentally, had Mossy's goal stood, Tipperary might not have achieved its '49 to '51 three in a row and Cork might have done a six in a row - '49 to '54.
On The 27th of August 2008 Maurice (Mossy) O'Riordan passed away in Newcastle NSW (Australia), where he had lived for some 40 years, after a severe stroke, He was 81 years old. Ar Dheis De go raibh a a hanam.