During a fourteen-year professional career he played for Fulham, Peterborough United, Barnet, Gillingham and Brighton & Hove Albion, and made over 300 appearances in the Football League.
Born in the Hackney district of London, Thomas began his career as an apprentice professional with Fulham in October 1984.
The Kent-based club was challenging for promotion from the Football League Third Division and manager Tony Pulis was looking to strengthen his team.
[2] Thomas remained with the "Gills" until the end of the 1997–98 season, but played only 30 matches,[5] his opportunities being restricted by a succession of injuries.
[2] One such injury occurred in November 1996 as the team were training for an upcoming Football League Cup match against Ipswich Town of the First Division.