Sunday's Athens derby was delayed after several Panathinaikos fans invaded the field to try and attack the Olympiakos players.
The fixture - known as the derby of eternal enemies - has a long history of violent clashes between the two sets of supporters and as Olympiakos players warmed up ahead of the game at the Stadio Apostolos Nikolaidis, home fans invaded the playing area and tried to assault them.
Police eventually were able to restore order, though, and the match kicked off around 15 minutes later than originally scheduled.
However, the drama continued when Olympiakos midfielder Pajtim Kasami was struck on the shoulder by a flare just before the start of the second half, resulting in another delay as the Swiss star received treatment.
In addition, the away side's coach Vítor Pereira had a lucky escape when he managed to get out of the way of a chair thrown in his direction by another Panathinaikos supporter.
Panathinaikos won the game 2-1 to move within three points of their arch-rivals at the top of the Super League but Olympiakos president Vangelis Marinakis felt the game was completely overshadowed by the behaviour of the home fans.
"Unfortunately we saw an atrocity for Greek football today," he told reporters.
"What we saw out there I don't think I could have ever imagined. Our players cannot play well in these conditions and are heroes. It is an unprecedented situation.
"I saw the players. Some are beaten, others are upset, others are shocked. We did not come for war, we came to play football."