Arsenal reached the halfway point of the Europa League group stage with a 100% winning record after benefiting from two own goals against reigning Norwegian champions Molde.
For the second time in three Group B games, the Gunners had to come from behind after Martin Ellingsen beat Bernd Leno from 25 yards following a superb pass by former Manchester United reserve player Magnus Wolff Eikrem.
With no video assistant referee system in operation, Eddie Nketiah had what looked like a legal goal disallowed for offside before Arsenal equalised at the end of the first half.
Kristoffer Haugen put past his own keeper while trying to intercept Nketiah’s pass to Joe Willock before Sead Kolasinac blazed a great chance over the bar.
The Gunners took the lead when Molde substitute Sheriff Sinyan turned Willock’s pass across the six-yard area into his own net.
Substitute Bukayo Saka picked out Pepe to make it 3-1 before Willock added a late fourth goal, Arsenal three points clear at the top of the group with three games remaining.
Arsenal, with two games to spare, could secure a place in the last 32 of the competition with victory in the return fixture in Norway on 26 November.
Mikel Arteta has now seen his side win three successive games in all competitions since they were undone by Leicester’s counter-attack last month.
Despite falling behind, Arsenal were able to brush aside their opponents without the need to bring on Pierre-Emerick Aubameyang, Alexandre Lacazette or Thomas Partey.
Arteta was all smiles at the end, fist-bumping Willock on the pitch after the full-time whistle with the 21-year-old’s hunger and desire helping his side to an important win.
The Gunners had fallen behind after failing to close down Ellingsen, whose excellent strike had Molde dreaming of one of the greatest results in their history.
It was the wake-up call the hosts needed, Arteta’s side playing with a higher intensity after equalising.
Arsenal’s future looks in good hands, Nketiah also impressing with his speed and work-rate while substitute Saka played a highly-intelligent pass to pick out Pepe for his goal.