The Group C clash saw legendary Panathanaikos coach Zeljko Obradovic return to the Greek capital, having led his former club to five Euroleague titles in 13 years at the helm.
However, the hosts were in no mood to roll out the red carpet as they tied the club record of 18 three-pointers, while Dimitris Diamantidis also became the first man to pass the 1000-assist mark in European basketball.
AJ Slaughter was also in fine form - weighing in with 23 points - as Panathinaikos built on their 59-36 half-time lead to secure their second triumph of the competition.
In Group D's only encounter of the day, Crvena Zvedza Telekom picked up a famous win against European champions Valencia.
Meeting for the first time since the 2008-09 season - when Valencia beat Zvezda twice in the Eurocup Last 16 - the hosts ran out 76-63 winners in Belgrade to extend their opponents' losing start to the campaign.
Elsewhere, in Group A, Real Madrid took on Nizhy Novgorod for the first time with the fixture going to form as last season's Liga ACB runners-up romped to a 112-83 win - Jaycee Carroll plundering 32 points for the hosts.
Dinamo Banco di Sardegna Sassari and UNICS were also in action, with a dominant second-half showing from the Russian side helping them to a maiden win of the season.
D'or Fischer top scored for the hosts with 14 as Sassari's losing streak was stretched to three matches.
Group A rivals Zalgiris battled to a hard-fought 65-62 victory against Anadolu Efes of Turkey.
Zalgiris leapfrogged their opponents into second as Edgaras Ulanovas finally came to the party. Having only contributed two points all season previously, he contributed 19 and seven rebounds this week to help his side record back-to-back wins.
Maccabi Electra continued their impressive winning run against Alba Berlin in the only game of Group B.
The Israeli side had not lost to their German opponents since 1997 - going on to win the next seven prior to Thursday's showdown at O2 World.
And Brian Randle was the star man for Maccabi, raining in 25 points for the visitors as Maccabi ran out comfortable 84-69 victors in the German capital.