Born in Glenbeigh, O'Riordan first enjoyed success at club level in 1956 when he won a Mid Kerry Championship title. He won three more divisional titles in a club career that lasted 20 years, as well as a County Championship title with Mid Kerry in 1967. O'Riordan made his first appearance for the Kerry senior football team in the first round of the 1961-62 league, ending his debut season by winning an All-Ireland Championship medal after lining out at right wing-forward in the final against Roscommon. He also won back-to-back Munster Championship medals before playing his last game in the fourth round of the 1964-65 league.[1][2]