Dodgy pass out almost cost his side within the first few minutes but appeared settled after that early blip.
Was uncharacteristically sloppy at times both on and off the ball, notably letting Machado in at the death of the first half. Consistent fouling afforded the opposition the chance to build attacks
Another game that will add to a swelling confidence. Progressive going forward while never looking in trouble with his defensive duties
Needless yellow on the half hour mark ensured that he was treading on eggshells for the remainder of the game but dealt pretty well with Olympiacos' at-times one dimensional attack. Spurned headed chance to kill the game off.
Was allowed to build up steam down the left flank and made the most of it. His constant bombing one was one of the more potent aspects of Arsenal's attack, while he was also sound defensively.
Always looked the dangerman for his team, constantly threatening the spark to bring Arsenal to life. That said, his otherwise flawless technique let him down when in front of goal early in the second half.
Short passes here and there didn't always come off in a performance that wasn't as magisterial as others he has produced this term.
Might see this game as an opportunity missed, with the game passing him by for large chunks. Failed to produce the dynamism brought by Abou Diaby this term but was busy nonetheless
Fired home when it mattered before turning provider for the second. Was mobile and elusive throughout, with his directness on the ball obviously unsettling his counterparts. Another strong performance which strengthens his current hold on a centre-forward starting berth.
Affected the game in his usual doggedly-efficient manner, firing home the all-important goal to restore Arsenal's lead. Could have perhaps made more from Gibb's omnipresence on the left byline though only came inside himself on the rare occasion.
Energy in closing down gave all his team-mates a lift early doors but failed to match this initial promise with any concrete product afterwards. A bustling display though probably not one many will remember
Arguably could have done better for both goals he conceded but that may be tough on the keeper, with both Arsenal goals struck well and on the ground. Otherwise performed reasonably well, commanding his area with authority
Sturdy defending throughout which was admirable given the manner in which Gibbs threw himself forward.
Was hounded by Oxlade-Chamberlain early on and never looked fully at ease from there on.
The game bypassed him for large parts, with his role chiefly reduced to work horse in the middle. Opportunities for him to build going forward were few and far between
Looked unsure of how to deal with the mobile centre-forward play of Gervinho but rarely lost out in aerial battles.
Couple of untidy moments early on were negated by phenomenal work rate as he became side's most influential player.
Combative in the middle of the park but the quality of Cazorla and Arteta eventually outshone him as Arsenal took fuller control of the game as it developed.
Often found himself in promising positions following Arsenal's laxness though could not muster the composure or technique to make anything of it - particularly when missing a sitter from six yards towards the end of the first half
Quality delivery led to his side capitalising on Arsenal's sloppiness but otherwise effected the game very minimally.
Very tidy finish with his head right at the end of the first half and was burly and unsettling most of the game. Looked as if he would be the one to drag Olympiakos level again after they went 2-1 down.
Short cameo but produced delightful dink to totally kill the game off
Missed two pretty decent chances to put the game beyond doubt, before flicking on a header to assist Ramsey's effort
Introduction brought instant energy as his side has begun to slightly flail. Constantly beat his man and produced a few chances during the shrot time he was on
Wasn't in any way able to change the pattern of the game that saw Arsenal emerge as the dominant force towards the end
Short cameo at the end but largely recreated the man he replaced, producing little of note down the left and having to concentrate fully on his defensive duties
Introduced for the last 10 minutes as Olympiakos sought a way to get back into the game but Arsenal managed to see it out efficiently