The match, which was scheduled to take place on Thursday evening, was called off after fans of the Piraeus club pelted the Panathinaikos bus with rocks as it neared the stadium, smashing a window.
Greece international forward Stratos Perperoglou and American forward Steve Smith were both admitted to hospital after complaining of eye pain but were later discharged, Panathinaikos team manager Manos Papadopoulos told reporters.
The general secretary for sport Panos Bitsaxis along with the police will meet officials from both clubs as well as league organizers ESAKE to decide on the rescheduling of the match.
"Olympiakos unequivocally condemns the actions of those unknown persons and expresses its indignation; we are happy to learn that all team members of Panathinaikos are in good health," said the club in a statement.
The violence came less than a week after Olympiakos triumphed in Europe's premier club competition, the Euroleague, against CSKA Moscow in Istanbul, taking over the crown from Panathinaikos who won the competition last season.
Greece's perennial sporting rivals were to face off in the first of a best-of-five series that will decide the domestic basketball champion for 2012.
Panathinaikos are the current holders and have won the last nine championships.