Douglas was a forward who represented Drogheda United, Bohemian F.C. and Bray Wanderers A.F.C. amongst others during his career in the League of Ireland. He signed for Bohemians during the 1990/1991 season and won the FAI Cup with Bohs in 1992. He was Monaghan's top league goalscorer in 1994/95.
He represented Ireland at Under-21 level.