We have our first win of the Mikel Arteta era thanks to a determined, energetic performance on New Year's Day.
Nicolas Pepe fired us ahead with a first-time finish after Sead Kolasinac and Pierre-Emerick Aubameyang had cut Manchester United open down our left.
Kolasinac made a storming run from left-back and stayed onside to receive a return pass from our captain before cutting the ball back for Pepe to finish.
Pepe, now full of confidence, tricked his way into the box to set up Aubameyang for a volley over the bar, and Alex Lacazette miscued a shot after turning past Harry Maguire.
You sensed we needed a second goal - especially after how Sunday's game against Chelsea panned out - and it arrived just before half-time.
Pepe was the provider with an excellent corner delivery, Lacazette's flicked header was pushed out by David de Gea, and Sokratis was on hand to volley into the roof of the net.
We were rather more circumspect after the break, happy to play on the break while United probed for a goal that would bring them back into the game.
But they never got it, thanks largely to a gutsy rearguard action that was epitomised by the tigerish Lucas Torreira in front of defence.
Three points, and a corner turned. This was the perfect start to 2020.
HOW IT HAPPENED
FOUR THINGS WE NOTICED
WHAT IT MEANS
Arteta freshened the team up after an exhausting battle with Chelsea on Sunday, making four changes.
One was enforced - the injured Calum Chambers making way for Sokratis. Elsewhere, Kolasinac came in for Bukayo Saka, Pepe replaced Reiss Nelson and Granit Xhaka started instead of Matteo Guendouzi.
Mesut Ozil, Pepe, Aubameyang and Lacazette started together for the first time.
We begin our Emirates FA Cup campaign on Monday with a home tie against Leeds United.
Then it's back to the Premier League and an away trip to Crystal Palace.
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