Old Firm Ultras were allegedly barred from entering Celtic Park after police corralled opposing fan groups ahead of the high-stakes derby, which Rangers won 3-2. Both Celtic's infamous Green Brigade and Rangers' Union Bears faced containment outside Celtic Park as away fans made their return to the match for the first time in over two years.

Violence erupted on Sunday, December 15, hours before the crunch match at Hampden Park in the south side of the city.

Celtic lost their second-straight Glasgow Derby. That has been rare in recent years. Even more worryingly, this defeat came at home and against a Rangers team that was 16 points behind them coming into the game.