Nacho Monreal cancelled out Marko Arnautovic's opener at the Emirates, before defender Issa Diop netted an own goal, with Danny Welbeck banging in a late strike
ISSA funny old game – and Arsenal’s season took a turn for the better thanks to an own goal by Issa Diop - before Danny Welbeck sealed the victory late on.
The West Ham defender marked his Premier League debut by diverting Alexandre Lacazette’s cross into his own net with 20 minutes to go.
Until then, the visitors had matched Arsenal in a game full of chances.
But it’s the Hammers who sit rock bottom after losing this early season six-pointer to leave them with three defeats from three games.
Pre-match rumours suggested Mesut Ozil had stormed out of training after a bust-up with new boss Unai Emery.
The German was not in the matchday squad and Arsenal were the better side until his replacement, Aaron Ramsey, had the ball in the net in the 11th minute only for it to be rightly ruled out for offside.
Then West Ham took the initiative.
Arnautovic had already hit the side netting before Felipe Anderson was allowed to run half the length of the pitch and exchange passes with the Austrian, who then stroked a 20-yard shot precisely into the bottom corner.
The travelling fans’ chorus of “How s**t must you be, we’re winning away?” soon backfired, though.
Henrikh Mkhitaryan played in Hector Bellerin down the right and former Gunner Lukasz Fabianski could only parry the cross to the edge of the six-yard box, where Monreal was waiting to smash the ball home.
The Hammers continued to threaten in an end-to-end spell, with Michail Antonio and Anderson having shots on target before Ramsey forced Mkhitaryan into a decent save.
And Robert Snodgrass had a great chance to put the visitors back in front in first-half stoppage-time when played in by Antonio, but Petr Cech dashed off his line to smother the ball.
Emery sent on Lacazette at the break and the chances kept on coming – for both sides.
Fabianski made a good save from a Shkodran Mustafi header, and two less spectacular ones to dent Lacazette.
But Arnautovic volleyed wastefully wide, then hit his shot too close to Cech after Anderson had found him at the end of another long run.
Some poor West Ham defending at the other end led to Arsenal's second goal. They failed to clear their lines properly and Lacazette made space for himself to strike the ball firmly across the goal.
It didn’t matter whether it was a cross or a badly-directed shot because it hit Diop and went in.
Diop made some amends by blocking an Aubameyang shot soon afterwards and Fabianski then saved superbly from Ramsey.
But West Ham did not threaten to snatch a point until Anderson stormed away on the break again only for substitute Lucas Perez, one of three ex-Arsenal players on the pitch for the visitors, to shoot badly wide.
And the result was sealed after Welbeck fired home in the 92nd minute after being found by Bellerin inside the box.
