Olympiacos moved two points behind leaders Panathinaikos with a 2-0 win at PAOK Salonika.
Djamel Abdoun and Kevin Mirallas got the goals in the opening 20 minutes before PAOK had Costin Lazar sent off on 76 minutes.
PAOK's defeat allowed AEK Athens to move above them and into third after the capital club won 1-0 at home to Panionios. Pantelis Kafes scored the deciding goal on 27 minutes.
Second-half goals from Xavier Umbides and Nery Castillo gave Aris Salonika a 2-0 win at FC Xanthi, who had Spiros Vallas sent off on 71 minutes.
Doxa Dramas remain rooted to the bottom as they lost 1-0 at Asteras Tripoli. Substitute Emanuel Perrone scored the winner on 54 minutes.
Kostas Mitroglou's 79th-minute penalty earned Atromitos a 1-1 draw at Panetolikos, who went ahead through Henri Camara on nine minutes. Mitroglou's game ended on a sour note, though, as he was sent off in stoppage time.