A
left back, Callaghan joined
First Division club
Fulham as an apprentice in 1962 and made his first senior appearances during the
1963–64 season. Callaghan made a career-high 52 appearances during the
1970–71 season and appeared in 45 out of 46 league fixtures, helping the Cottagers to promotion back to the
Second Division with a second-place finish. Although not a regular goal scorer, he scored a key goal in the 1971–72 Second Division season, securing a 2–2 draw at Charlton Athletic that saved the club from relegation. Callaghan made his final appearances for the club during the
1972–73 season and was forced to retire in 1974 due to a back injury. He made 336 appearances for Fulham across all competitions. == Managerial and coaching career ==