The OM boss was critical of his side's lacklustre performance which saw another late goal conceded at the Stade Velodrome.
Olympique de Marseille boss Didier Deschamps was left frustrated with his side's performance as a late lapse in concentration enabled Olympiakos to come away with a 1-0 victory in Champions League Group F on Wednesday evening.
OM were eight minutes away from sealing the point they needed to progress to the last 16, but Giannis Fetfatzidis's fine strike saw Ernesto Valverde's men avoid elimination from the competition. Steve Mandanda produced countless saves to deny the Greek champions, but ultimately his efforts proved fruitless.
And the 43-year-old coach expressed his frustration after the match.
"A draw would have sufficed, but I cannot say that the victory of Olympiakos is undeserved," he told Canal+ after the game.
"Without [Steve] Mandanda, they could have [scored] much sooner. The collective performance is grossly inadequate in relation to the goal that there was this evening.
"We just lost an opportunity to qualify for the knockout stages and I am very disappointed, but there is no resignation. We'll have to forget this defeat."
Souleymane Diawara was equally critical of the team's performance, telling the club's official website: "Instead of playing simple, we have complicated the task. In the second period, Olympiakos did the right thing and we did not react. I think we did not play a European Cup match tonight; it was more like a friendly match.
"We did not have the commitment, there was no aggression. We missed envy. There were too many missing things tonight to win. "
Marseille still have their fate in their own hands as they travel to Germany to face Dortmund on matchday six. Olympiakos host Arsenal, with OM needing to equal the Greeks' result to qualify.
Didier Deschamps' men return to league action this weekend hosting Ligue 1 leaders PSG on Sunday in the Derby de France.