Arsenal lost their second straight Premier League match following a 3-2 defeat to Chelsea.
Arsenal supporters expecting a response following last week’s 2-0 defeat to Manchester City were greeted with an opening 30 minutes to forget.
The Gunners fell behind in the ninth minute, Marcos Alonso finding space behind the defence before teeing up Pedro to score.
Pierre-Emerick Aubameyang should have equalised for the visitors but he skied his effort over the bar from close range - and it was 2-0 52 seconds later.
Cesar Azpilicueta played Alvaro Morata in and the Spaniard freed himself from Shkodran Mustafi before slotting the ball past Petr Cech.
Unai Emery’s side was in disarray. It might take a while for him to fully ingrain his methods but Arsenal were even getting the basics wrong.
And yet they managed to get back into the match.
Ozil missed the final 20 minutes
Henrikh Mkhitaryan fired a left-footed shot past Kepa Arrizabalaga in the 37th minute, just moments after missing a sitter.
And Alex Iwobi fired home from Mkhitaryan’s delivery to make it 2-2 at half-time.
It was a wild half of football, featuring poor defending and missed sitters.
The game slowed down in the second half as both managers plotted just how to win a difficult match.
Emery decided to replace Granit Xhaka with Lucas Torreira at half-time, a decision that went down well with arsenal supporters.
And another call that the Arsenal boss made was to haul Mesut Ozil off in the 68th minute, with Aaron Ramsey coming on in his place.
The German playmaker struggled to make an impact. He didn't influence the match as Emery would have liked, with Arsenal under pressure in the second half, wasn't going to help out defensively.
It left Arsenal fans pleased as they realised Emery won’t be afraid to make such big decisions in high-profile matches.
Arsene Wenger always seemed reluctant to take Ozil off even when the midfielder struggled. With Emery, it seems that won’t be the case.
Ozil had better get used to things under Emery.
Unfortunately for Emery, his tactics didn't work. Alonso netted the winner late on as a difficult start to life in the Premier League continued for the former Paris Saint-Germain boss.