Consecutive big-game defeats to Borussia Dortmund and Chelsea put Arsenal in a bit of a slump. Fans grew more nervous than they had been in months, and many wondered whether Arsenal were capable of beating elite teams.
Their defeat of Liverpool last weekend went a long way toward answering those questions.
The Gunners dominated the Reds in much the same fashion that Dortmund did at the Emirates two weeks ago. In both cases, the winning team's movement and passing was quicker and more incisive, indicating a gulf in quality that was ultimately reflected in the scoreline.
Arsenal have really left themselves with a lot to do in this, the most important game of the group stage thus far.
Losing is utterly out of the question. Three teams are chasing the two top spots in Group F, and all have six points. Arsenal will play both teams before the round is over—Dortmund on Wednesday and Napoli in the final game.
A victory would obviously catapult the Gunners back to the status of group favorites and give the team a massive injection of swagger ahead of a somewhat-less-daunting-than-usual trip to Old Trafford this weekend.
Because of the tight schedule and the fact that Arsenal are in an exceptionally difficult period of fixtures, Arsene Wenger must wisely pick his team.
There is no question about who will start in goal. Wojciech Szczesny was once again exceptional against Liverpool, notwithstanding one moment of madness when his pass squarely hit Daniel Sturridge but bounced right back to him. Unless Szczesny is clinically insane, there is no way that was intentional. Regardless, he was as assertive in his penalty box as he has ever been, and continues to justify Wenger's faith in him.
You can be equally sure that Bacary Sagna will assume his place at right-back once more. The Frenchman has not shown any hint that he might be aging this season and is miles ahead of Carl Jenkinson.
In the absence of a natural right-winger, Sagna has needed to push forward constantly and has flourished as a right-back who can dominate in all facets of the game.
After Per Mertesacker and Laurent Koscielny contained the potent striking partnership of Sturridge and Luis Suarez, both have earned the right to play against Dortmund.
Wenger might have a case for inserting Thomas Vermaelen in Koscielny's place, as the latter did not have his best game of the season against Liverpool. But a merely above-average game for the Frenchman is still excellent, and his tenacity will be vital to containing Dortmund's well-oiled attacking machine.
He and Mertesacker will need to be tremendously disciplined for the full 90 minutes—switching off and leaving open space for even a brief moment can be deadly, as Robert Lewandowski emphasized during the clubs' prior meeting.
One new player will be introduced to the back four, though. After sitting behind the stellar Kieran Gibbs all season and contenting himself with late-game appearances off the bench, Nacho Monreal looks set to start, after Gibbs picked up a calf injury against Liverpool.
The fact that Arsenal can directly replace Gibbs with Monreal is indicative of the excellent depth built into the team.
Monreal certainly has his work cut out for him. As there will be no natural left-winger in front of him, he will have to surge forward quite often. But because the likes of Marco Reus will be harassing him all game, he cannot let his defensive guard down.
In the absence of Mathieu Flamini and Vermaelen, and after his best performance of the season last weekend, Mikel Arteta will surely shield the defense and wear the captain's armband.
Arsenal will hope he has enough left in the tank to deal with Dortmund's persistent threat after exerting himself so much against Liverpool. He popped up in all areas of the pitch in that game and frequently cut out Liverpool's attacks with all the brawn and guile of a defensive midfielder.
The atmosphere at Signal Iduna Park is legendary, and Dortmund's fans get rowdier than perhaps any others in Europe. Arteta's calm marshaling will therefore be crucial to keeping the side composed and organized.
Aaron Ramsey, fresh off yet another scintillating display, is virtually certain to play ahead of Arteta. Unlike the Spaniard, Ramsey played against Chelsea last week, so fatigue might become a significant issue for him.
Arsenal need him to be in the best shape possible. As the Gunners' top goalscorer this season, his presence is crucial to putting the ball in the back of the net, but the Welshman's box-to-box energy and relentless pursuit of the ball is equally important.
Dortmund's tiki-taka-esque passing and movement at the Emirates was dizzying at times, and pressing them in all areas of the pitch is crucial to disrupting their rhythm.
Mesut Ozil will have to play better than he did during the first leg if Arsenal are to be more threatening when they win the ball back. The German star was languid and generally anonymous in just the sort of game for which he was bought in to give Arsenal an edge.
As Bleacher Report's James Dudko correctly pointed out (despite much rebuke), Ozil has struggled to adapt to the Premier League since his arrival. Though the Dortmund game—arguably his worst since transferring to Arsenal—was played in the Champions League, Ozil has not caught up with the Gunners' pace quite yet.
He will adjust, in time. A player of his extraordinary talent surely can, and that talent will earn him a starting spot against Dortmund. But Ozil needs to assert himself more than he has for Arsenal to match Dortmund's attacking potency.
Wenger does not have much choice about who will start on the wings.
Theo Walcott and Lukas Podolski are nearing the end of their respective stints on the sidelines, but they will both be unavailable for the Dortmund clash. Thus, Santi Cazorla and Tomas Rosicky are the only two options available, unless Wenger wants to risk Serge Gnabry.
The manager could have it worse. Rosicky's energy and constant harrying of Liverpool's midfield was a massive boon to Arsenal last weekend. He did his best against Dortmund two weeks ago, but no one else had the energy or will to join him.
He will be a huge asset on the right wing, back in his old stadium. But Santi Cazorla will probably outshine him.
Though only partially fit, the Spaniard had an immediate and dramatic impact when he was brought on during Arsenal and Dortmund's prior meeting. His ability to control the ball in tight spaces and find teammates took a ton of pressure off the Gunners at a time when they could not stop giving the ball away.
Who will win?
Cazorla does not provide much width on the left but can dart inside or out and will. When playing teams as good as Dortmund, instant game-changers like him are absolutely essential.
Selecting a striker will be equally easy. Even if Arsenal had a player who could capably replace Olivier Giroud, he would not deserve to be dropped.
In many ways, the Frenchman is the linchpin of the Gunners' attack. He has a clinical eye for goal, of course, but can physically impose himself upon a defense like no other player in the team. Battering rams are common in English football, but Giroud is distinguished by his ability to pair power with technical nous. His analog, Lewandowski, plays the same role for Dortmund.
For both sides, then, the performance of their primary goalscorers will go some way toward determining which side leaves Signal Iduna Park in prime position to advance to the Round of 16.