This paper considers the economic impact of the sports tourism expenditures associated with regular season sports competition. In particular the sports tourism characteristics of the supporters of two largest football clubs in Scotland – Celtic FC and Rangers FC – are investigated. Both of these clubs are based in Glasgow, but play matches (and draw supporters from) across and outside Scotland. The paper quantifies the direct, indirect and induced effects of this expenditure using a novel extension of a two-region Input Output (IO) table for Glasgow and the rest of Scotland. The IO system is used to calculate net additional economic activity, in terms of GDP and employment, from gross and displaced activity at different regional levels