Arsenal outdo Chelsea for force and will in unusual display of unity as Maurizio Sarri's Blues continue to lack focus

Alexandre Lacazette and Laurent Koscielny struck in the first half and the visitors had no answer as the race for the top four intensified

An impressive new focus from Arsenal, after a week where their new regime threatened to go into tail spin, but ended up only exposing the problems in the new Chelsea.

There is also a fresh energy to the battle for the Champions League places. That is the greater importance of this surprisingly easy 2-0 win for Arsenal, that came out of such difficulties. They were difficulties so pronounced - and so much greater than the expected departure of head of recruitment Sven Mislintat - that Unai Emery had warned before the game that defeat would pretty much finish their top-four chances. If that was a message to his squad, as much as anyone else, it got through. They responded. They rallied together, and showed an energy beyond Chelsea here.

There was no such response from Maurizio Sarri’s side. To pretty much anything, least of all short set-pieces. They were even more tepid than the performance level that has become worryingly typical of late.

This game again showed why they needed Gonzalo Higuain - or just something different in attack - although Chelsea’s issues went beyond the lack of a centre-forward

Arsenal’s two centre-forwards in Alexandre Lacazette and Pierre-Emerick Aubameyang - a Mislintat signing - were meanwhile rampant in the first half, with that this time enough to win the game. They showed a force and will Chelsea just couldn’t match, for any period of the game.

It was effectively won in the first 20 minutes, with Arsenal’s early siege just blowing Chelsea away.

Sarri’s side never mustered any such power, and that should pose greater questions.

One of the reasons cited for Chelsea’s recent drop-off in scoring has been Sarri “tightening up at the back”, but there was no evidence of that here.

There was only evidence that they’d possibly never seen a short set-piece before, something that Emery had apparently spotted in preparation for this match. Without the need for spying, of course.

How else to explain, though, the number of times that Arsenal went short with attacking set-pieces? How else to explain the extreme problems Chelsea had with that?

Kepa Arrizabalaga could only keep Emery’s side out with heroics for so long. It was a compliment to the Spanish goalkeeper up to then, mind, that Lacazette made sure his finish was right in the top corner and pretty much perfectly unstoppable. It of course arrived from a short corner, Hector Bellerin working the ball into the box for Lacazette to take, turn and power in.

The finish for the second goal wasn’t quite so deliberate, but was from another short set-piece. A free-kick was this time passed rather than crossed, the simple variety of this apparently so bamboozling the Chelsea defence that they weren’t prepared for when a cross actually did come in. Neither was Koscielny, really, but that didn’t matter as he had thrown himself sufficiently forward to get sufficient contact with his shoulder. Kepa couldn’t stop this one from the centre-half.

Alexandre Lacazette celebrates his opener (Arsenal FC via Getty Images)

This wasn’t because Arsenal were calculatedly playing for set-pieces, of course. It was because they were just blowing Chelsea way, and in the process exposing so many other problems.

David Luiz once more looked uncomfortable in a two. That to be fair is something that hasn’t been so apparent of late, but the problem of players being played out of position became much more apparent in this game. That was the case with Hazard, N’Golo Kante and Marcos Alonso.

While this was a day when every single Arsenal player knew precisely what they had to do, you just couldn't say the same of Chelsea.

This is not to say that there is anything wrong with Sarri’s long-term approach. It’s actually to his credit that he shows such a commitment to an idea. It’s just impossible not to think there could occasionally be a touch more compromise, especially when big games are going like this.

The value of the compromise he had initially made, mind, had been completely blown away. If Chelsea were suddenly as porous as they’d been in the first few months of the season, there was no positive flipside. There was no attacking abandon.

There was just nothing all over the pitch.

That should be all the more frustrating for Chelsea because the Arsenal backline of late has looked like it would buckle under any kind of pressure. That was never tested, but it was telling they looked panicked with the merest hint of some impetus from Sarri’s team.

Eden Hazard and Chelsea players look dejected after going 2-0 down (Getty Images)

Even within an Arsenal blitz, Pedro was still presented with a one-on-one against Bernd Leno that he took an odd decision with, before Marcos Alonso hit the post from a header.

It was one of the few moments when Chelsea played with any kind of focus, in great contrast to Arsenal.

They played like they had a point to prove, and with all the focus that involves. They played like a unified team again.

They play that resurgent Manchester United next. It is not in the league, but it may well be telling.

Arsenal’s response told here.

If only they could recruit this kind of focus more regularly. Chelsea meanwhile just need to show any.