Born in Linton, Morpeth, Northumberland, Kelly started his career at Watford, who then played in Division Three South.
Kelly recalled of the events: "On the Friday I signed for Blackpool, within 24 hours I had travelled from London to Bramall Lane and was playing against Sheffield United.
We got beaten 2–1 – and we desperately needed the points too – but meeting my new colleagues in the dressing room and having my first experience of Blackpool's polished style of play helped to make it an otherwise unforgettable day.
"[2] He scored his first goal for the club later that season, on 26 February 1955 in a 3–1 defeat to West Lancashire rivals Preston North End.
He returned to the Fylde coast playing non-League football in the Lancashire Combination with Fleetwood in the 1966–67 season.