Alexandre Lacazette inspired Arsenal to a memorable victory to keep their Champions League hopes alive.
Gunners boss Unai Emery warned before the game that defeat would spell the end of Arsenal ’s top four chances – and the players responded with an energetic, all-action win.
Lacazette got Arsenal off to a flying start with a 14th minute opener before Laurent Koscielny scored a second before half time when the ball went in off his shoulder.
Chelsea came back with a better performance in the second half, pinning Arsenal back but the home side held on.
The big setback for Arsenal was Hector Bellerin being carried off in the second half with what looked like a nasty injury.
Here’s five talking points…
Arsenal formation the star
Unai Emery has tinkered and toyed with different formations this season – and might just have stumbled across something.
With Chelsea using Eden Hazard as a false nine, Arsenal had no need to go three at the back so returned to a flat back four but, even more interestingly, was the front line.
Arsenal have looked unbalanced and awkward at times as Emery has tried to squeeze both Alexandre Lacazette and Pierre-Emerick Aubameyang into the same starting XI, generally one ends up playing wide.
But Arsenal the time got them both up front with Aaron Ramsey playing just behind. Surely the 4-3-1-2 might be the solution in the long term.
If they are still here, use them
Aaron Ramsey is leaving in the summer, deal done with Juventus and it would be easy to make him a bit-part player.
But while they are still there, why not use them? Ramsey played just behind the front two and his energy and dynamism gave Arsenal a new dimension.
It feels like the same with Mesut Ozil. He was back on the bench but while he is the club’s top earner on £350,000-a-week and there are no takers in sight, why not just use him?
Energy is key for the Gunners
Arsenal are at their best when it’s high tempo, fast and all action. They were like this against Tottenham and now Chelsea.
Arsenal are a work in progress under Unai Emery. They were awful last week, terrific this week and the running theme here is obvious: intensity.
Slow and plodding at West Ham , fast and tenacious against Chelsea. Emery’s training is tough and intense. That is to make sure the players play fast. They need to do it more often.
Jorginho’s amazing stat
Chelsea’s No5 is supposed to sit deep and dictate the play. Trouble is, he sits deep in midfield and always passes sideways or turn backwards.
The most incredible stat of all is that he has yet to provide a single assist and has not scored since the opening day at Huddersfield .
For Chelsea, you simply cannot afford the man at the heart of midfield to offer so little. I admit I thought he was great at first, but he must offer more.
Chelsea’s defence looks too vulnerable
Forget Chelsea’s lack of strikers, their defence looks a shambles. They are trying to address the centre forward issue by signing Gonzalo Higuain, but they could do with some defensive reinforcements – or they are in danger of missing out on top four.
David Luiz always has a mistake in him. Cesar Azpilicueta’s form has dipped, Antonio Rudiger is rugged and tenacious while Marcos Alonso is better going forward.
They were so well drilled under Antonio Conte but now look vulnerable and creaky under Maurizio Sarri. They need a new defensive leader – and quick.