Olympiakos 0-3 Arsenal: Gunners advance to Champions League last 16
Olivier Giroud inspired Arsenal to complete a Champions League group stage comeback as his hat-trick at Olympiacos sealed their place in the last 16.
Going into the game having lost three of their previous five fixtures, the Gunners needed to win by two goals or more at the Karaiskakis Stadium or better the 3-2 defeat they suffered at home to the Greek champions in September.
With seven key first-team players missing through injury, Arsene Wenger recalled Theo Walcott after his recovery from a calf problem - but it was Giroud who would produce the goods when it mattered as Arsenal made light work of a seemingly difficult task to seal a 3-0 win.
For Giroud it would have been all the more sweet given he had been sent off in the 2-1 defeat at Dinamo Zagreb which started a run of poor results that led to tonight's scenario.
Arsenal become just the eighth side to advance through their group having taken three points or fewer from their opening four matches and Wenger will now be hoping to avoid the big names as they will come up against a group winner in the next round.
The Gunners took their time as they felt their way into the contest but finally stirred as Joel Campbell's cutback was struck goalwards by Mathieu Flamini, with a deflection off Manuel da Costa taking the ball onto the crossbar.
But the opener came just moments later as Mesut Ozil produced a sublime pass to set Aaron Ramsey away.
His near-post cross was met by the head of Giroud and the ball squeezed over the line as Olympiacos goalkeeper Roberto was unable to deal with it.
It was the hosts who nearly got the game's next goal as another sloppy pass from Hector Bellerin left Arsenal exposed and Brown Ideye's cross was turned inches over his own crossbar by Laurent Koscielny as the game remained finely poised at the interval.
There was concern for Giroud at the start of the second half as he fell awkwardly on his ankle while helping out his defence.
But he soon got himself back on the pitch and soon doubled Arsenal's lead after another well-worked move.
Ozil again started everything with a clipped pass to Campbell, with the former Olympiacos loanee controlling well under pressure before sliding a perfect pass into the path of Giroud for the France striker to sweep home.
Walcott came close to adding a third to give Wenger's men some breathing space but his effort was blocked behind for a corner.
Petr Cech then showed just why Wenger was so keen to sign him in the summer as he pushed away a curling Kostas Fortounis shot with the hosts looking for the one goal they needed to advance at Arsenal's expense.
Ideye should have done better when picked out in front of goal but Per Mertesacker was on hand to clear before the former West Brom forward could pounce.
Olympiacos had begun to set siege to Cech's goal but they were undone when referee Nicola Rizzoli pointed to the penalty spot as Nacho Monreal's shot was blocked by the arm of the diving Omar Elabdellaoui.
Giroud duly despatched the resulting penalty to complete his hat-trick and send Arsenal into Monday's draw for the first knock-out stage as they saw out the remainder of the contest with minimal fuss.
Arsenal boss Arsene Wenger believes his side could be "dangerous" in the latter rounds of the Champions League - so long as they get there.
The Gunners face Olympiacos on Wednesday night knowing that even a victory may not be enough to see them qualify from Group F.
Having lost three of their opening group matches, including a 3-2 home defeat to their Greek opponents in September, Arsenal go to Piraeus as outsiders to progress.
They must beat Olympiacos by two goals, or match or better the result from their previous meeting, to seal qualification from their group for the 16th consecutive season.
And Wenger feels that, if they can get the required result in south-west Athens, Arsenal can sustain a challenge to win the competition - even if he admits there are a number of teams who are more fancied.
"Of course we can be dangerous if we go through because we come from far back," he said.
"Overall if you look at the numbers since the start of the Champions League group stage, we have played with 10 men in Zagreb, we scored an own goal at home to Olympiacos.
"Every single game we were a bit unlucky but if we get through we will be dangerous that is for sure.
"At the moment we have two or three super-favourites and whoever gets through tonight or tomorrow will have to chase them."
If Wednesday's game at the Karaiskakis Stadium takes plenty of twists and turns as both sides look to join Bayern Munich in next Monday's draw, Wenger knows his players must be able to alter their gameplan on the pitch.
"We have to put every scenario in our head, it is important we focus on the performance," he added. "The results come if we play well so lets focus on that. When the goal comes I don't know but if we play well we have a chance to score.
"Mentally, you prepare yourself to adapt to every situation and give the right response to every situation you face.
"We will have to adapt to what is happening on the pitch and to all of the scenarios, accept them and respond."
Wenger has no fresh injury concerns ahead of the game and is likely to field the same starting XI that secured a 3-1 victory over Sunderland on Saturday.
Theo Walcott is again likely to only make the bench as his comeback from injury continues, while Mathieu Flamini and Aaron Ramsey have been backed to continue their partnership in the heart of midfield.
"Midfield is important in games like this," Wenger explained.
"Flamini and Ramsey will have to play an important part in a game of this stature but I'm confident that they can and will."