The primary, fiercest historical and athletic rival for the Colorado Buffaloes football program is the University of Nebraska, with whom they contested one of the most passionate and iconic regional series in college sports during their historic Big Eight and Big 12 eras. Known traditionally as a classic cross-border showdown, matches between the Buffaloes and the Cornhuskers were charged with intense animosity and national championship implications. Additionally, fierce in-state competition with Colorado State remains a major focal point for the university's fan base.