[1] Born in Waterford, Dunphy first arrived on the inter-county scene at the age of seventeen when he first linked up with the Kilkenny minor team, before later joining the under-21 side.
As a member of the Leinster inter-provincial team on a number of occasions Dunphy won one Railway Cup medal as a non-playing substitute.
Dunphy's father, Eddie, his uncles, Joe, William and Wattie, and his brother, Dick, all played for Kilkenny at different stages.
Reigning champions Bennettsbridge provided the opposition, however, a narrow 2–8 to 1–8 victory gave Dunphy a Kilkenny Senior Hurling Championship medal.
A 3–13 to 0–15 victory gave Dunphy an All-Ireland Minor Hurling Championship medal, while he also had the honour of lifting the Irish Press Cup.
He was a regular during the subsequent National Hurling League campaign and made his senior championship debut on 27 June 1965 in a 1–20 to 3–8 Leinster semi-final defeat of Dublin.
Richie Power gave a masterclass of hurling, including scoring the winning point deep into injury time, to secure a 2–16 to 2–15 victory.
Richie Hogan proved to be the hero for Kilkenny, as his point, a minute into injury time, earned "the Cats" a 1–18 to 3–12 draw.