Fans of Greek Cup finalists Panathinaikos and PAOK have clashed with police inside the Olympic stadium delaying the kick-off then forcing the match to be suspended after the game's only goalscorer was apparently hit by a missile.
Eventually Panathinaikos were able to complete a 1-0 win.
Violence broke out an hour before the match was due to start as spectators, delaying the kickoff.
Panathinaikos and PAOK fans tried to enter the area of empty seats separating them, and riot police responded with tear gas to break up the crowd.
The final was then interrupted after Aitor Cantalapiedra scored from the penalty spot for Panathinaikos in the 34th minute and PAOK fans threw objects onto the pitch.
Cantalapiedra was reported to have been hit by a missile after players celebrated near the PAOK fans.
PAOK fans also clashed with police outside the stadium during halftime, a police official said.
Greek soccer has been plagued by violence on and off the pitch and authorities have repeatedly promised to clean up the game. Fights between football fans are frequent before or after a game and it is not uncommon for a match to be disrupted by crowd trouble or a pitch invasion, despite the heavy fines.
The government has tightened rules to combat violence at sports events following the killing of a 19-year-old soccer fan this year in what was believed to be an attack by rival supporters.
