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In the 1973–74 season Middlesbrough ran away with the old Second Division finishing 15 points clear from second place Luton Town (Under the old points system of 2 points for a win.) They were promoted to the First Division on 23 March 1974, finishing the season conceding only 30 goals, keeping 25 clean sheets in a 42-game programme. Maddren's final appearance for Boro was on 3 September 1977 against West Bromwich Albion. He was only 26. Maddren had a persistent knee injury and he often played games when in pain. An operation was unsuccessful and he retired in 1979.