An Olivier Giroud hat-trick was enough to see Arsenal progress to the knockout stages of the Champions League at Olympiacos's expense this evening.
The hosts started the game positively as Seba missed the target on a couple of occasions, while former Fulham target Pajtim Kasami tried his luck from outside the penalty area, only to fire wide.
Arsenal took a while to grow into the contest, but came agonisingly close to taking the lead on 25 minutes when Mathieu Flamini struck the crossbar, before Olympiacos goalkeeper Roberto kept out a Giroud header.
Arsene Wenger's side took the lead on 29 minutes, as Aaron Ramsey picked out Giroud with an inviting cross, before the French striker headed past Roberto.
The Gunners appeared to be in control of the game after breaking the deadlock - with Theo Walcott missing the target after a powerful run - but they almost conceded an equaliser before the break when Laurent Koscielny turned a Ruben Pardo cross over his own bar.
The visitors made a stride towards qualification in the second half, as Joel Campbell picked out Giroud, who placed a finish past Roberto to double Arsenal's advantage.
Olympiacos almost ended their opponents' hopes of qualification moments later, when Arsenal keeper Petr Cech denied Dimitrios Siovas from close range, before the former Chelsea man produced a good save in the top corner to keep out Konstantinos Fortounis.
Arsenal were awarded a penalty on 66 minutes when Omar Elabdellaoui was deemed to have handled the ball inside his own box from a Nacho Monreal cross. Giroud stepped up, and fired past Roberto to seal his hat-trick and all but confirm his side's progression to the knockout stages.
The hosts were unable to trouble their opponents for the remainder of the match, as the Gunners sealed progression from Group F.
