This was not a night to challenge Mikel Arteta's beliefs. The overriding message was that he can trust the Arsenal players he already trusts.
The 36-team, never-ending league phase format of the Champions League does not serve up jeopardy. Clubs have eight bites at the cherry. It is fairly difficult to be knocked out.
This match, a 3-0 Arsenal win, was initially played in that mould. The Gunners knew defeat would hold no real meaning.
The concern for Arsenal, and for Arteta as he ponders future lineups, is that this should have been a night of jeopardy for those who came into the side.
Arsenal's fringe forwards had an ideal platform from which to force their way into Arteta's Premier League plans. Instead, this performance highlighted the two-tier nature of Arsenal's attack.
Arsenal did not wake up until Kai Havertz, Martin Odegaard and Bukayo Saka came off the bench
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Arsenal opened the scoring while Havertz, Saka and Odegaard stood on the touchline waiting to come on, but it was not until they were introduced that the Gunners really got going.
Saka assisted and then scored from a Havertz cutback. Odegaard dictated play. The zip and flow was back. That was a welcome sign, particularly the composure from Saka after a run of poor finishing.
However, Arsenal did not need further proof that the likes of Saka and Odegaard can deliver decisive moments.
As much as he would like to, he cannot always play them. With Arsenal looking to go deep in all four competitions, Arteta needs to trust his squad. There was little here to suggest the fringe cast can be relied upon when it really matters, on nights with far more riding on it than this.
Viktor Gyokeres has barely started a match this season but if this was an audition, he should not be expecting a callback. The same goes for Mikel Merino, though his is a more unique situation.
Unique: Mikel Merino did not impress against Lille
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As one of Arteta's finishers, Merino has repeatedly delivered off the bench. He is calm on the ball and brings real control, particularly when trying to see out a match.
He also has a knack of scoring as a substitute, as he did three times for Spain over the international break.
However, as a starter in midfield, the same impact is not there. Merino looked ponderous and too often slowed the Gunners down. He was unusually disappointing in front of goal, too, nodding a tame header straight at Berke Ozer and later slicing over.
Especially in a game where Arsenal are dominating the ball and needing to break down a compact defence, Merino in that Odegaard midfield role does not look effective.
The Spaniard looks far more suited to being a finisher than a starter. Gyokeres, meanwhile, does not look particularly capable of doing either for Arsenal.
In the opening 45 minutes, Gyokeres managed seven touches, none of which were meaningful. As has been a persistent theme, he was incredibly poor at holding the ball up and using his body for a man of his size.
By the time he came off, just after the hour mark, he had registered no shots and just one touch in the opposition's box. Six Arsenal players managed more.
There are often calls from some sections of the Arsenal fanbase for the team to play more to his strengths, but it is hard to make a case for what those are.
Eberechi Eze struggled for much of the night, too, but he then stepped up when the changes were made. He scored from Saka's cross, as Arsenal's cavalry lifted the standards of those around them.
Those stars waiting in reserve were a crutch Arsenal always knew they could lean on. The issue is the team do not look capable of standing up without them.