1. Wenger will find it hard to drop 'outstanding' Campbell
Does Wenger play Ramsey on the right flank at Norwich City on Sunday, or start with Campbell as a reward for his display
Aaron Ramsey returned from injury as a second-half substitute against Dinamo Zagreb, and it's Joel Campbell's position in the team that looks most under threat by his comeback. Ramsey had largely been playing on the right flank before his injury but Campbell played so well in this game that Arsene Wenger opted to keep him on the field for the full 90 minutes, with Ramsey introduced on the left. Campbell provided the fine slide-rule pass for Alexis Sanchez to slot home Arsenal's third goal and was bright throughout – completing 21 passes in the attacking third, a total surpassed only by Mesut Ozil.
He is also improving significantly in his defensive duties, a weakness in his game highlighted in previous fixtures, succeeding with 4 out of 6 tackles. "I believe he had an outstanding game," said Wenger.
The Costa Rican had been dropped for Saturday's defeat at West Brom after a couple of indifferent performances, but his impressive performance against Dinamo Zagreb has now given Wenger a dilemma. Ramsey also did well when he came on, completing 23 of 24 passes. With the Welshman approaching the point where he is fit enough to start matches again, does Wenger play Ramsey on the right flank at Norwich City on Sunday, or start with Campbell as a reward for his display in the Champions League?
2. Flamini proves able replacement for Coquelin
The Frenchman gave the ball away only once in the opening 35 minutes, completing 29 of 30 passes as the Gunners moved 2-0 in front and effectively killed off the game
Another man playing for his place was Mathieu Flamini, who didn't dominate the headlines after this match but was quietly effective as he stated his case to be the regular replacement for Francis Coquelin, who has been ruled out for three months with a knee injury. It was Mikel Arteta who came on for Coquelin at The Hawthorns on Saturday, only for the Gunners to concede twice – with Arteta putting the ball in his own net for the goal that would ultimately consign Arsenal to defeat. The Spaniard was then forced off through injury just after half-time, after which Flamini used the ball intelligently and completed an impressive 47 of 49 passes.
This fixture against Dinamo Zagreb was Flamini's chance to really tie down a starting spot before Arteta's return from a short-term calf problem. The Frenchman gave the ball away only once in the opening 35 minutes, completing 29 of 30 passes as the Gunners moved 2-0 in front and effectively killed off the game.
In total he completed 54 of 58 efforts, with all 11 passes in the final third finding an Arsenal shirt, as well as making 6 ball recoveries and 3 interceptions. Wenger used the final few minutes of the match to look at Calum Chambers in a defensive midfield role, but Flamini seemed to have done enough to keep himself ahead of both Chambers and Arteta in the pecking order after this steady display.
3. Arsenal wouldn't be alive without Sanchez
The Chilean's assist for Ozil's opener was his fourth in five Champions League games this season and he then netted twice himself, meaning he has now been involved in 7 of Arsenal's 9 European goals this season
Arsenal still have plenty of work to do in their final fixture if they are to reach the last 16, needing to win by two clear goals or by scoring at least three at Olympiakos. That they still have any chance at all of getting through is largely down to Alexis Sanchez. Ozil may be Arsenal's assist king in the Premier League right now, having set up 9 goals in the Gunners' last 7 league matches, but it is Sanchez who has taken that role in the Champions League. The Chilean's assist for Ozil's opener against Dinamo Zagreb was his fourth in five Champions League games this season, and he then netted twice himself, meaning he has now been involved in 7 of Arsenal's 9 goals in the Champions League this season.
Sanchez and Ozil each had 4 shots – Arsenal had 16 attempts in total – with Ozil also creating 4 chances. Ozil completed 31 passes in the final third – 10 more than anyone else on the field.
4. Arsenal's defence was much improved
Arsenal had conceded 10 goals in 4 Champions League games this season going into this fixture, with only Maccabi Tel Aviv and BATE Borisov conceding more. They may not have been facing Europe's finest opposition in Dinamo Zagreb, but they still looked much steadier in defence than they had done in Croatia.
Per Mertesacker and Laurent Koscielny were largely untroubled in the centre of defence, while right-back Hector Bellerin fulfilled his defensive duties as well as darting forward whenever possible. The Spaniard attempted 4 take-ons and had made 18 passes in the final third by the time he was substituted with eight minutes to go to rest his legs – only surpassed by Ozil and Santi Cazorla at that point in the game.
Left-back Nacho Monreal set up the Gunners' second goal after a smart interception – one of 4 he made during the match – and he led the match stats for ball recoveries (9) and blocked crosses (5).
5. Cazorla recovered from penalty misery
Cazorla was another player to have a good night, as he recovered from the misery of his penalty miss at The Hawthorns. The Spaniard was omnipresent against Dinamo – he completed 7 of 7 take-ons, 4 more than any other player on the field, as well as completing the most passes (66) and making 7 ball recoveries.