Alexandre Lacazette was on target but despite a bright attacking performance we were beaten by Newcastle on a frustrating afternoon on Tyneside.
The France international gave us an early lead after combining well with Pierre-Emerick Aubameyang, but Ayoze Perez equalised before the interval and then Matt Ritchie struck the winner for hosts.
There was genuine excitement before the game at the prospect of seeing Aubameyang and Lacazette starting together for the first time – and it did not take them long to show why.
With just 14 minutes on the clock Shkodran Mustafi played a pinpoint lofted pass to Aubameyang to the left of the area and after taking a touch, it looked like the forward would try his luck.
Instead the Gabon striker curled a lovely left-footed pass towards the back post where Lacazette was racing in, and he diverted it into the roof of the net.
Aubameyang saw a shot deflected just wide moments later, before then setting up Iwobi for an effort that was held by Martin Dubravka.
We looked in control, but just before the half-hour mark Newcastle equalised as DeAndre Yedlin curled one in from the right and Perez nipped in at the near post to beat Petr Cech.
Calum Chambers twice went close before the interval, while Premier League debutant Joe Willock dragged a good opportunity wide as we continued to press.
Iwobi flashed one over the bar just after the restart, but the second half was not quite as open as the first as the game became more of a midfield battle.
Neither side were finding it easy to create opportunities, but with 22 minutes remaining Ritchie put the hosts in front when finished calmly from 12 yards out.
Kenedy then hit the bar with a deflected shot before Perez hit the sidenetting moments later as Newcastle tried to put the game to bed in the closing stages.
We pushed and probed in the final moments but could find no way through, as we slipped to another defeat on the road.
HOW IT HAPPENED
See how the match unfolded and get the standout stats with our play-by-play commentary.
WHAT IT MEANS
We host West Ham United at Emirates Stadium next Sunday in the Premier League, before returning to Europa League action four days later against Atletico Madrid.
We drew 0-0 against West Ham at the London Stadium in December, before beating them 1-0 in the Carabao Cup less than a week later courtesy of Danny Welbeck’s first-half goal.
AUBA AND LACA WATCH
There was real intrigue at a first start for the Lacazette-Aubameyang partnership, and they looked a constant danger at St James’ Park.
Here are the pair’s key moments:
7 - Lacazette drags a shot wide from the edge of the area
14 - Mustafi plays a long ball into Aubameyang in the area, he takes a touch and hooks it across goal for Lacazette to fire in
17 - Rapid break and Iwobi finds Aubameyang flying up the left and he cuts inside but his shot is deflected behind for a corner
21 - Aubameyang flicks it on for Iwobi in the box, he wriggles to find some room and toe-pokes it at goal but it’s saved
43 - Lacazette pounces on a defensive error and races in on goal and looks to find Willock in the area, but he slices his shot at goal
84 - Lacazette latches on a loose ball in the area after Dubravka fails to hold a high ball, but his shot from a tight angle hits the sidenetting
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