Olympiakos retain top spot
Luciano Galletti set Zico's team, who have qualified for the last 16 of the Champions League, on their way with a 37th-minute opener.
Brazilian midfielder Dudu scored either side of halftime to complete a resounding victory which moved the Reds on to 36 points after 14 matches. Panthrakikos have just two points following 12 defeats and two draws.
New Panathinaikos coach Nikos Nioplias got his reign off to a winning start at Iraklis on Saturday with Sotiris Ninis scoring the only goal of the game in the 73rd minute.
The Greece Under-21 coach took charge on Tuesday, replacing Dutchman Henk ten Cate.
In Thessaloniki, Hector Cuper, the former Valencia coach, was left labelling Aris's 1-0 home defeat by Asteras Tripolis "a disgrace."
Nigerian Shaloze Udoji Chigozie scored the only goal in the 12th minute and the defeat left Aris down in eighth spot, six points adrift of city rivals PAOK who occupy third place.