Duncan succeeded Ron Ashman, as player-manager, although at this time he had no managerial experience, he was known for a distinguished playing career both north and south of the border. His enthusiasm for the game and fresh ideas no doubt won him the approval of the board.
Duncan was born in Lochee, Scotland in 1949 and made his way through junior football to eventually sign for Dundee in April 1966. During the next eight years he gained Scottish League representative honours, and a Scottish League Cup winners medal in 1974.
He was lured away to Tottenham Hotspur in 1974 for £125,000, and then left for Derby County in 1978 for £150,000.
Sadly, Duncan's career became dogged by injury and Derby had to suffer a financial loss when he left for the manager's seat at the Old Show Ground in 1981. The legacy of his injuries were such that he played little in Scunthorpe United colours. The Iron were just about holding their own, but the 1981/82 season was a time of crisis and upheaval. There was virtually nothing in hand to buy new players and old contracts meant that Duncan had to soldier on with that available.
United slumped as the end of the season approached, and not until the last couple of months was Duncan able to bring in a number of men on short-term contracts. Alas, this could not save the club from finishing next to bottom in Division Four.
Duncan's managerial career began to blossom in the 1982/83 season when he brought in a number of new players including Steve Baines, Les Hunter, Neil Pointon, Dennis Leman, Martin Fowler and Noel Parkinson. Overnight the team was transformed as they headed towards the top of the league. A good FA Cup run plus a potential promotion place looked to have secured Duncan's future at the Old Show Ground.
Unfortunately it all turned sour after defeat in the FA Cup third round replay at Grimsby, when it would appear that there were differences between the manager and Chairman which led to the shock dismissal of Duncan in February 1983.
Many considered that Scunthorpe had lost an excellent young manager, and his departure was mourned on the terraces of the Old Show Ground. He, however, went onto control the affairs of Hartlepool United, Ipswich Town and Chesterfield, twice, where he steered his Division Two team to the FA Cup semi-finals in 1996/97.
Upon leaving professional football management, John demonstrated his unwavering passion for the game and coaching, working with budding players and coaches at Loughborough University. In his role with the LMA, John acted as a mentor and confidante to a vast number of coaches and colleagues and became a respected voice in English football. For many years, he imparted his football expertise to support the development and improvement of refereeing standards, in his role as LMA Technical Manager.
Rest in peace, John.