In a frantically paced first half that simmered with promise, the home team were the first to convert their impressive build-up play into something tangible.
Ilhan Fakili was both creator and scorer, as the French-born Turkish U21 international exchanged passes with Junior Olaitan on the edge of the area, and rolled a cool finish beyond Marseille goalkeeper Jeffrey de Lange from eight yards out.
On the back of three consecutive losses in Ligue 1 and trailing in the white-hot cauldron of the Tupras Stadyumu, Marseille proved themselves a stubborn foe to extinguish and, 14 minutes after going behind, the French side were level.
Keyliane Abdallah had room to run in behind the defence after Besiktas were dispossessed in midfield, and once Himad Abdelli found him with a pinpoint ball, the 20-year-old produced a tidy finish to silence the home crowd.
On the stroke of half-time, smart play from Dusan Vlahovic saw Orkun Kokcu played in on goal, but De Lange raced off his line to thwart the Black Eagles. However, the Dutch stopper’s efforts were soon in vain after the restart, as Les Olympiens' flame was truly doused within 13 minutes of the restart.
First, Vaclav Cerny fired the hosts into the lead when he curled an unstoppable strike on the angle into the far corner, and three minutes later former Marseille man Amir Murillo rose to head home from a corner and flatten his former employers.
There was no hint of a repeat of the visitors' fightback in the first half, as the Turkish side poured on the misery, as Fakili crashed a shot against the bar with De Lange beaten.
The final pounding moment of humiliation eventually came with nine minutes left, as Ernest Poku raced onto a through ball and drilled home a fourth goal, plunging Bruno Genesio’s difficult start at the helm of Marseille into new, murkier waters on the banks of the Bosphorus.
Flashscore Man of the Match: Orkun Kokcu (Besiktas)