Celtic reached the semi-finals with a 4-2 victory on spot-kicks, which followed a 0-0 draw in a typically fiery Old Firm derby.
Cvancara scored the winning penalty for the away team, but just as they began to celebrate, the tension among the fans erupted. A large number of Celtic fans rushed onto the pitch, with some of them throwing pyrotechnics. Rangers fans at the other end of the stadium also entered the field during the chaotic scene.
A person got very close to Celtics players and staff, but was then tackled to the ground and taken away from the court. Police and staff then had to erect a barrier between the two groups of fans.
When interviewed after the game, bloodstains could be seen on Cvancara's jersey. However, it is currently unclear how the bloodstains were caused.