I think the biggest followed foreign sport for a while was Kabaddi in the '90s.
Basketball, baseball, and (cough
) football do have a following but you'd be hard pressed to see someone wearing any fan kit in the UK or know who they are. Maybe in some cities they may have a greater presence, but not where I've lived.
Kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi, kabaddi!