The Gunners should have scored more than once in the opening stages but the biggest missed chance was, improbably, Pierre-Emerick Aubameyang side-footing wide from close range.
Benfica didn’t have too many chances in the first half despite plenty of possession, though Granit Xhaka almost gifted them an equaliser in the closing stages - only for Alejandro Grimaldo to fail to take advantage. Less than 10 minutes after the restart they were ahead, however, Pizzi scoring a penalty after Emile Smith Rowe handled in the box.
An immediate response saw Bukayo Saka equalise from close range, before Aubameyang spurned another couple of big openings to give his team the lead and both sides settled for a draw ahead of the second leg next week.
Here are five things we learned from the match.
Arsenal have been so inconsistent this season that it’s basically impossible for them to ‘target’ winning anything. The last eight games across all competitions are an indication of that: three wins and as many defeats, despite a four-game win streak before that - which itself came on the back of one win in six. It’s just that type of campaign.
Here, though, Mikel Arteta made it quite clear that he’s going all-in to stay in the Europa League, probably seeing it as the Gunners’ only real route back into European competition next season.
They were at full strength with the available players, an unchanged line-up from the win over Leeds, and perhaps the manager will feel largely vindicated after Arsenal edged the game on chances created and hit the away goal to be favourites at the start of the second leg.
After a few games working his way up to fitness and earning a place in the team, Martin Odegaard now quickly looks an immovable part of the furniture.
He was comfortably the Gunners’ biggest threat in terms of creating chances, getting the team on the front foot and keeping Benfica’s back three guessing where he was going to appear and which way he’d slide the ball in, with his close control and willingness to beat players on the run every bit as impressive as his end pass.
Cedric claimed the assist for the equaliser, but it was again the Norwegian who found the space and the rapid timing of his pass to free the left-back for a routine cross into Saka.
Fans will already be wishing they had been able to negotiate a buy clause in the loan deal, but his future is rightly well above this level.
The Portuguese side are far from out of this tie, but it should be noted they are well below their best this term and Arsenal must be extremely confident about progressing in the second leg.
Just 11 wins in 19 games domestically leaves them fourth in the table - 13 points off Lisbon rivals Sporting CP, who lead the Liga NOS.
For context, the last time Benfica finished outside the top two in the league was 2009, well over a decade ago.
This is far from a vintage version of this famous side - like Arsenal themselves, in fairness - and, in the second leg in Athens, the Gunners must make sure they take advantage of having the away goal and their opponents being under far greater constant pressure than Arteta’s team have been.
After five games out through injury, Scottish defender Kieran Tierney made his comeback for the Gunners in the second half, coming off the bench for the final half-hour.
It has been remarked upon in several quarters that the Gunners not only missed his tenacity in their own half of the pitch, but also his on-the-ball quality and vision in attack.
A little rustiness was to be expected, but he also showed signs of the clever link play he’s capable of and good energy levels.
Similarly, Gabriel Martinelli played his first Europa League game of the season, appearing off the bench for the first time in four games. There’s so much more to come from him once full fitness is reached and he could play a crucial role in this competition - if the Gunners progress.
Big calls required
The Europa League, with its extra knock-out round compared to the Champions League, sees the second leg played just one week from now. It means a non-stop run of high-stakes games, with Arsenal facing Manchester City in the league at the weekend.
Arteta has a big call to make: City are in outrageously good form, so is it worth resting one or two players to stay fresh for Europe, where Arsenal have more chance of having a meaningful end to the season?
An admission of defeat in the team-sheet isn’t a good look, but it might be time to get practical in this fractured and frustrating campaign. Even beyond the second leg, it’s Leicester next in the league, so the matches won’t be getting any easier any time soon.
Arsenal’s season, and the manager’s progress 18 months into the job, will likely be determined in large part by the calls he makes over the next 10 days or so.
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