Olympiakos shook off an early Besiktas lead on Thursday to emerge victorious from yet another Euroleague game in Istanbul, where a few months ago it had claimed its second European crown.
The Reds won 79-60 for their sixth victory in nine games in the second group stage.
Still looking for its first victory in this second round, Besiktas led at the start, edging Olympiakos by two (15-13) at the end of the first period.
Yet led by an impressive Josh Powell, who made seven out of eight two-pointers for a total of 16 points on the night, Olympiakos advanced 38-30 at half-time and never looked back playing against a side that does little more than making up the numbers in the Euroleague top-16.
In his debut with Olympiakos, Doron Perkins played for five and a half minutes but scored no points, although the Reds had 10 other players on the scoresheet.