A three-goal blitz in the opening 22 minutes laid the foundation for another comfortable Europa League win.
Teenage Brazilian forward Gabriel Martinelli got us going with a fantastic near post header from Kieran Tierney's pinpoint, whipped in cross.
Barely two minutes later the 18-year-old doubled the lead with a cool low finish after shifting the ball onto his right foot inside the box. It was his second brace in only his second start for the club, following his double against Nottingham Forest in the Carabao Cup.
We were rampant, and as the rain poured down in north London, the goals continued to flow. Joe Willock got his name on the scoresheet next, finishing well after Reiss Nelson's shot was deflected into his path.
The young Gunners, showing 10 changes from Monday night's draw at Old Trafford, were in complete control.
There was no let up after the break. Martinelli turned provider for the fourth goal, scooping the ball over the keeper for Dani Ceballos to convert from virtually under the crossbar.
It was the Spain international's first goal for us, and he deserved for another tremendous midfield showing.
Martinelli was desperate for his hat-trick, and came close several times to claiming the matchball.
Captain Hector Bellerin also nearly capped his first start for nine months with a late goal, but we had already done more than enough to secure another three points in Europa League Group F.
HOW IT HAPPENED
WHAT IT MEANS
We stay top of Group F after two games played, three points clear with a plus seven goal difference.
We're at home again this Sunday to face Bournemouth in the Premier League, for a 2pm kick-off. We are looking to extend our excellent home record against the Cherries, having won all four of our Emirates Stadium meetings to date.
Our next appointment in the Europa League is in three weeks' time, at home to Portuguese side Vitoria.
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