Ferguson amassed over 1,000 domestic appearances in a career where he played for Ards, Glenavon, Linfield and Lisburn Distillery, and scored a total of 563 goals, placing him 2nd behind Jimmy Jones (648) on the list of all-time goalscorers in Northern Irish football.
Glenn was born on 10 July 1969 in the Ulster Hospital Dundonald to Thomas and Ida Ferguson and is the youngest of their three children.
On 1 December 2006, he scored his 226th goal for Linfield, which took his career total to 476, making him the third highest scorer in the history of the local game, behind only Jimmy Jones and Joe Bambrick.
On 2 February 2008, during the CIS Cup Final, Ferguson came off the bench with 20 minutes remaining with Linfield trailing 2–1 to Crusaders.
[8] Ferguson made his final career appearance on 30 April 2011, playing for Lisburn Distillery in their 4–3 home win over Cliftonville.
on 8 January 2012, and won his first trophy as manager when the Sky Blues defeated Ferguson's former club Linfield in the County Antrim Shield final on 27 November 2012.