A fairly dismal first 45 minutes saw the two best moments fall for the home team, with Sheriff Sinyan missing from one yard out and goalkeeper Runar Runarsson missing the ball entirely after running out of his box to clear for the Gunners.
Nicolas Pepe finally curled in the opener just moments into the second half, though, before Joe Willock put a great cross over for Reiss Nelson to score from minutes later.
There were further chances for Eddie Nketiah and Alexandre Lacazette, before sub Folarin Balogun sealed the routine win and Arsenal’s qualification from the group phase with a neat finish on the turn.
Here are five things we learned from the game in Norway.
In the league, Arsenal have scored a solitary goal - and that from the penalty spot - in their last 475 minutes of action.
As the half-time whistle sounded on Thursday, their impotence in front of goal transcended competitions to make it no goals and only seven shots on target in 225 minutes on the pitch across their last three games.
And the efforts on target here were almost not worthy of the name, with a tame Nicolas Pepe effort straight at the 'keeper the most dangerous of the bunch.
Mikel Arteta might be still in the process of improving his side’s overall approach, but it’s hard to shake the feeling he is hindering their attacking approach at present, with much of the build-up play predictable and in front of opposition defences in recent games.
They needed to take more risks, make better runs and find the earlier pass - and it finally started to happen in the second half.
Of course, Arsenal are a far superior team to Molde and quality was always likely to tell - the bigger question was of who would would step up to make the difference.
From very early on it was apparent Nicolas Pepe was keen to be that man, wanting not only to put in a good performance for his own first-team prospects, but also to make amends for his weekend moment of madness.
He cut infield to fire in a couple of shots in the first half, sighters of sorts, before starting the second half with two similar belters - one which rattled the crossbar and the second which found the back of the net.
Pepe’s work rate, running and willingness to try the unusual pass made him the stand-out on the night - it’s just a shame he’ll now be banned for the next three domestic games.
Squad points proven
A couple of the younger Gunners might feel they continue to knock on the door for regular inclusion thanks to their European exertions.
On the night in Norway it was Reiss Nelson and Joe Willock who impressed most - not for the first time for the latter in particular.
There’s a real hunger about Willock’s movement going forward, a desire to get into the area and beyond the striker, but it doesn’t come at the expense of being in position defensively.
His cross for Nelson’s goal was a great example of his vision and technical ability, while Nelson himself was one of Arsenal’s more progressive players in both halves. Given the team’s struggles to find regular scoring chances, they must both hope for inclusion in Premier League games in the coming weeks.
With a win, Arsenal can consider it job done - they are into the knock-out phase in the new year.
There’s no point holding punches: this group was a real shocker, offering absolutely no challenge to the Gunners with sides from Norway, Ireland and Austria - six wins from six can be considered standard, if they achieve it.
The important task was merely to qualify, but the better positive is doing so while keeping squad members involved and resting a few who have been overworked elsewhere.
Arteta now gets a free pass for two fixtures essentially, with some youngsters perhaps in line for inclusion before the somewhat more relevant business of the latter stages begins in 2021.
Perhaps the third goal gave a glimpse of who the next batch of youngsters to get their chance will be.
Emile Smith Rowe has long been tipped to make a spectacular breakthrough for the Gunners, but he has had to be patient with a loan spell or two and a gradual inclusion at first-team level.
The attacking midfielder has to find his own role in the team, which doesn’t habitually play with a central No. 10 under Arteta, but he can certainly fill in across a variety of roles - and there’s scope to experiment with the last two Europa games, of course.
Meanwhile, goalscorer Balogun was rumoured to be close to a summer exit amid a contract dispute, but he scored his first senior goal here and showed plenty of forward movement - there’s never any shortage of excitement over young talents who can find the back of the net.
One set up the other for the 3-0 clincher and perhaps both might feature more heavily against Rapid and Dundalk.
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