Despite significant European success during the 1970s and early 1980s, the late '80s had marked a low point for English football. Stadiums were crumbling, supporters endured poor facilities, hooliganism was rife, and English clubs were banned from European competition for five years following the Heysel Stadium disaster in 1985. The Football League First Division, which had been the top level of English football since 1888, was well behind leagues such as Italy's Serie A and Spain's La Liga in attendances and revenues, and several top English players had moved abroad.
Try to answer this question if possible (otherwise reply "unanswerable"): Why were the English clubs banned from European competition in the 1980's?
English clubs were banned from European competition for five years following the Heysel Stadium disaster in 1985.