 He made his debut on 15 April 1951 when he scored five points in an 8-08 to 0-03 first round defeat of Seandún and was also amongst the scorers when Glen Rovers lost the final to Sarsfields.Clifford was still just 19-years-old when he lined out in his second senior final in 1953, ending the game with his first winners' medal after scoring a goal in the 8-05 to 4-03 victory over Sarsfields.Glen Rovers retained the title after a five-point win over Blackrock in the 1964 final, with Clifford claiming a second successive winners' medal before ending the season by completing the double after winning a county football championship medal with the Glen's sister club St. Nicholas'.