With both Greek teams already eliminated from the upcoming Euroleague playoffs, Panathinaikos scored a face-saving win against visiting Armani Milano on Thursday, while Olympiakos succumbed to host Real Madrid on Friday.
The Greens fought back from 20 points down to beat Armani 86-83 in overtime in their last home game of the season.
Welcoming back Nemanja Nedovic from a long absence, the Greek champion saw qualified Armani rally to a 42-22 lead late in the second quarter that finished 46-29.
However an unlikely comeback had Panathinaikos peg the Italian team down to just 24 points in the second half and force overtime with a 70-70 regulation result, before claiming its 11th victory in 31 games.
Mario Hezonja paced the Greens with 17 points, including the crucial basket that sent the match to overtime, with Ben Bentil adding 16.
Olympiakos was always the underdog in the game in Madrid that was meaningful only for the host, and predictably went down 72-63.
In a conspicuously low-score game in Madrid ,the Reds played second-fiddle to a more determined as well as nervous Real, that uncharacteristically focused more on its defense.
The Greeks trailed by 10 at half-time (36-26) and had notched up only 38 points after three quarters (53-38), only to reduce their arrears somewhat in the last period.
Sasha Vezenkov virtually had a one-man show for Olympiakos, being its only player in double figures (22 points) in this 18th loss for the Reds in 33 matches.