Greek Super League clash between Olympiacos and Panathinaikos had to be suspended after a Panathinaikos player was struck by a firework thrown at him by a fan.
The incident took place 5 minutes into the second half with the score level at 1-1 between the two rivals.
As the Panathinaikos players were warming on the touchline, Spanish star Juankar was struck by a firecracker thrown from the crowd.
He fell down to the floor injured and the 33-year-old received treatment before he was taken away on a medical cart and later to a hospital.
The match was suspended after the players went down in the dressing room and refused to come back out to play.
The clash between the two Greek teams is one of the biggest and fiercest rivalries in Europe and it is often marred with incidents.