By Josh James at the Borisov Arena
We will need to win by at least two goals at Emirates Stadium next week to stay in the Europa League, after a hugely-disappointing defeat to BATE Borisov.
We struggled to get going all evening, unable to take our first-half chances, and then unable to respond to the home team’s headed goal just before half-time.
Alexandre Lacazette was dismissed late on for a flailing arm to compound our misery.
On a poor playing surface, the first half was fairly scrappy, though the hosts went close a couple of times, most notably when Nemanja Milic hit the post from close range. They grew into the game as it progressed, having weathered our bright start.
Henrikh Mkhitaryan could have put us ahead in the first couple of minutes, but his shot was saved at close range after being set up by Sead Kolasinac.
But our best chance of the half fell to Lacazette, although the striker failed to get his header on target after Kolasinac found him with a good deep cross from the left.
We were made to pay, falling behind to virtually the last touch of the half. Igor Stasevich - who had racked up six assists in the group stage - was on the money again, floating in a perfect free-kick which was headed home by Stanislav Dragun.
It was the first goal we had conceded in the competition since matchday one back in September - a run of 495 minutes.
We came out with renewed determination after the break, and had the ball in the net, only for Lacazette to be flagged offside.
Former Gunner Alex Hleb was withdrawn before the hour mark, to applause from both sets of fans, but at 37 his powers had unsurprisingly waned from the player who helped us reach the Champions League final in 2006.
Unai Emery made changes of his own, bringing on Pierre-Emerick Aubameyang, Lucas Torreira and Denis Suarez. But we still looked laboured and slow in possession.
Our frustration continued to grow, illustrated up when Lacazette was sent off for swinging an elbow towards Aleksandar Filipovic late on.
It summed up a hugely disappointing night in Belarus.
HOW IT HAPPENED
WHAT IT MEANS
We will need a drastically improved performance next week in the second leg in order to progress. Without scoring an away goal in Belarus, it means we need to win by at least two at Emirates Stadium next Thursday.
With no game this weekend due to the FA Cup, our next fixture is the return leg of this tie, kicking off at 5.55pm at Emirates Stadium on February 21.
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