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Chelsea v Arsenal first of six games
Alonso strikes winner from Hazard's assist
Chelsea had 24 shots, Arsenal 15
Sarri's Chelsea have won their opening two league games
Emery's Arsenal have now lost to Man City and Chelsea
Chelsea 2-0 Arsenal
*copy and paste* Chelsea get in behind Arsenal again.
Willian sprints to the byeline and picks out N'Golo Kante in the box, but the Frenchman - playing in a more advanced role - has his shot blocked by Shkodran Mustafi.
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Dennis: Mikhitaryan misses from the same spot as Aubameyang
Rob: Anyone told Arsenal that they're not playing with rugby posts?
Eddie: LOL.. entire forward line for Arsenal!! This lot are embarrassing themselves out there.
Chelsea 2-0 Arsenal
Arsenal look like they've gone backwards since last season.
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James: Arsenal are actually worse defensively now than they were under Wenger. I’m not sure how that’s possible but Emery is giving it a good go!
Chris: Emery's tactics so naive! Playing far too high a line. 2-0 down, could be 5-3!
Chelsea 2-0 Arsenal
Oh my goodness, this is getting beyond a joke.
Pierre-Emerick Aubameyang missed a bad one earlier and Henrikh Mkhitaryan now does the same.
The former Manchester United man times his run into the box, but blazes a first-time shot into the stand from six yards out.
Chelsea 2-0 Arsenal
Arsenal boss Unai Emery looks a lost man on the bench.
Welcome to the Premier League, sir.
Image source, Rex Features#bbcfootball or text 81111
Michael: This is the season Arsenal fans realise how good they had it with Wenger.
Marsel: Arsene Wenger just sitting in his French beach house, sipping wine, with a huge grin on his face.
Chelsea 2-0 Arsenal
Granit Xhaka in booking shocker.
Arsenal's Swiss international is given a yellow card for a late challenge on Pedro.
Chelsea are making fun of Arsenal at the moment.
Chelsea 2-0 Arsenal
Marcos Alonso has been directly involved in 19 Premier League goals since his Chelsea debut in September 2016 (13 goals, six assists).
That is six more than any other defender in the English top flight.
No wonder Real Madrid are after him.
Image source, PAChelsea 2-0 Arsenal
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Chelsea 2-0 Arsenal
Phil McNulty
BBC Sport chief football writer
No wonder Unai Emery turned away with an expression of pure anguish on his face as Alvaro Morata made it 2-0 to Chelsea. He should have been celebrating the equaliser seconds earlier only for Pierre Emerick Aubameyang to miss a sitter.
What is it they say about fine margins?
Chelsea fans now rubbing it in by chanting "Are You Wenger In Disguise?" in Emery's direction.
Chelsea 2-0 Arsenal
Chelsea have scored with both of their first two shots on target.
Clinical
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Josh: Credit to Morata, brilliant play. Never been convinced by Mustafi and that further highlights his weaknesses
Hassan: That goal is very important, especially for Morata's confidence.
Jake: Cesar Azpilicueta assisting Alvaro Morata..... where have we seen that before I wonder?
Image source, Getty ImagesChelsea 2-0 Arsenal
John Southall
BBC Radio 5 live football reporter
The Arsenal team is not massively different and is the same side as last season.
Both sides are getting round the back and I can't see this staying 2-0.
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Belete: That is how you finish.
Ash: Pierre-Emerick Aubameyang misses a sitter and Alvaro Morata punishes him and Arsenal seconds later
Wasiyallah: Pierre-Emerick Aubameyang did Alvaro Morata.
Alvaro Morata
Can you believe it???
Shambolic, embarrassing defending from Arsenal, they should have levelled but instead fall further behind.
Cesar Azpilicueta on the ball deep in his own half, pops the ball over the top for Alvaro Morata to run on to.
A man bereft of confidence has plenty to do but keeps his composure, turning inside of Shkodran Mustafi and rolling in a finish past the helpless Petr Cech.
Chelsea 1-0 Arsenal
An absolute shocker from Pierre-Emerick Aubameyang, I'm talking bloopers reel, that's how bad it is.
Hector Bellerin sneaks behind Marcos Alonso and pulls a perfect pass back for Aubameyang, who lashes over from six yards out.
Image source, PAChelsea 1-0 Arsenal
Now Arsenal break forward, but Pierre-Emerick Aubameyang's shot from the angle causes Kepa Arrizabalaga no problems.
Chelsea 1-0 Arsenal
I can't believe how easy Chelsea are finding it to get in behind Arsenal, a bit more quality on the final ball and the hosts could be out of sight.
Full-back Hector Bellerin cannot cut out Willian's pass, but Marcos Alonso's cross it too long.
Image source, Getty Images#bbcfootball or text 81111
Ollie: As a Spurs fan it pains me to say it but Jorginho is really, really, really, really, really good.
Conor: Jorginho is absolutely fabulous in there.
Oli: Seen more good things by Ross Barkley in 10 minutes than the whole of last season.