Panathinaikos missed the chance to extend their lead at the top of the table as they went down 2-1 at PAOK Salonika.
Pablo Garcia and Zlatan Muslimovic scored either side of an equaliser from Djibril Cisse to lift third-placed PAOK level on points with Olympiacos in second.
Panathinaikos's third defeat of the season meant their lead at the top of the table remained at two points.
AEK Athens, 11 points further back in fourth, beat Aris Salonika 1-0, Pantelis Kafes with the goal.
Elsewhere, Asteras Tripoli held Atromitos to a 0-0 draw despite playing for half the game with ten men following the 45th-minute dismissal of Sokratis Fitanidis.
Basement-dwellers Panthrakikos won 2-0 at struggling Larissa thanks to a second-half brace from Steve Leo, while Panionios claimed a 3-2 win away to Giannina.
