Inside-forward Carlin came through the junior ranks at Anfield but only made one first-team appearance for the club, in a 2-2 draw against Brighton at Anfield on 10 October 1959. A promising youngster who had represented his country at schoolboy and youth levels, the pint-sized dynamo played 445 matches and scored 74 goals in all four divisions of the Football League. He was transferred to third division Halifax Town in August 1962 who were relegated at the end of the season.

Carlin's career took an upward turn when Brian Clough's Derby signed him in August 1968 and Carlin helped the Rams to win the Second Division. He was a regular for one season in First Division before being sold to Leicester who subsequently won the second division title. Again Carlin didn't stay for long in the top-flight as he was sold to third division Notts County in September 1971. He retired from playing after being at Cardiff City in the 1973/74 season. He went on to run a bar in Majorca for fifteen years and was a newsagent in Derbyshire. He passed away on 10th June 2024 aged 83.