John Pearson Duncan (22 February 1949 – 8 October 2022)[3] was a Scottish football player and manager.

After a brief spell at Hartlepool United, Duncan was appointed Chesterfield manager in the summer of 1983 and led them to the Fourth Division title in 1985.

Duncan led Ipswich to top-half finishes in the Second Division but was dismissed in 1990 after failing to lead promotion challenges.

[5] After leaving Ipswich, Duncan became a teacher at a Suffolk school before returning to Chesterfield in February 1993.

[5] In his second spell at the club, Chesterfield won the Division Three playoffs in 1995[5] and reached the FA Cup semi-finals in 1996–97, losing to Middlesbrough in a replay.