In the Guardian weekly podcast from Thursday there was the following exchange about Arsenal*:

James Richardson: They’ve got strength on the bench. They’ve upgraded their team on the field: with Sanchez doing better in the striking role (if you like) than Giroud (arguably) was doing, Mustafi looking better than Mertesacker, Xhaka looking like an upgrade on.. well I was going to say Jack Wilshere but he was never there. And yet when James was saying that he believed, Philip, you… an ironic kinda “poof” escaped your lips, why? Philippe Auclair: No no no! “I want to believe.” I think Mustafi is absolutely crucial and he’s why my opinion has changed slightly since the beginning of the season. Before the arrival of Conan (this is how I heard it and from now on we should call him Conan -Tim) Mustafi I thought “nah, it won’t be their year” but I have to agree with everything James has said. In terms of the squad, the quality of the squad is genuinely one of the very best in the League. Absolutely, without a doubt. James Richardson: mmm. I’m just thinking about how we are going to look back on this conversation in January? Philippe Auclair: He’s now got Xhaka, he’s got Coquelin, he’s got Elneny. When was the last time Arsenal has had three defensive midfielders who were actually defensive midfielders? When was the last time that Arsenal had two very very good keepers? Which is the case. You look and the possibilities up front as well, they have loads of possibilities. James Otherguy: Right but they’ve been here before though. Philippe Auclair: And we are talking about the team that is still waiting for Aaron Ramsey to come back, who can be a very important player in the second half of the season. So, yeah, I can understand why people would be optimistic.

January is now. Arsene said that Santi Cazorla suffered an Achilles injury, possibly in the same place as last season and that leaves questions for me about the Arsenal bench.

But first, I have to agree with the guys on the pod. Let’s start at the back.

Auclaire is big on Mustafi and for good reason: Mustafi and Koscielny complement each other and complement Arsenal’s playing style. Arsenal like to play a high defensive line, or more appropriately, Wenger likes to play an aggressive defense. This typically means stepping in to intercept the ball.

However, when one player steps to intercept, if he misses, that opens up problems in behind. Which is why Mustafi and Koscielny augment each other nicely: both can step and both have the speed to cover if there is an error. In the past, Koz had to cover for Mertesacker, who was slow to recover and any missed interception or tackle caused panic. But more than just cover, Koz also had the responsibility of stepping up and taking the passes away and he often led Arsenal in interceptions. This led to a situation where Koscielny was both the stopper and the cover.

This season, Mustafi is making more interceptions than Koz but not by a whole lot, they are 3.2 to 3 respectively. Mustafi is leading Arsenal in tackles per game (3.4) and is tackling at a high rate, having missed just 2 of his 19 attempts and meanwhile, Koscielny has been freed up to make more blocks and his blocks per game are up to 1. They are feeding off one another; one steps, the other covers and the same in return.

Both of these players are also capable of taking the ball out of the back and making long, vertical, passes on the ground to bypass the opposition midfield and get the Arsenal attack started.

Where they are going to struggle is with aerial duels. Mustafi is above 50% this season (12/22) and Koscielny is at 57%, just about his career average. As I pointed out in the post-match breakdown against Swansea, neither man was really challenging for some of the aerials and Swansea generated two wide-open big chances off headers. Middlesbrough is going to be Arsenal’s biggest test in the air so far this season: they are 2nd in the League in aerials per game, Negredo (their forward) is 4th in the League in aerials won, and they have scored 4 of their six goals off headers with 3 of those coming from set plays.

Still, there is no doubt that this is exactly how Arsene Wenger wants Arsenal to play football at the back.

As for the midfielders, I’m hesitant to call Elneny a “true defensive midfielder”. He is a strong runner and a shy tackler – he tackles at about half the rate that Xhaka and Coquelin do on a per90 basis. He is more like Cazorla in his defensive stats and that makes sense because I see him more as a backup for Cazorla. With injury to Cazorla revealed today, and with Ramsey still at about 90% fitness, Elneny will probably get the start this weekend.

As I’ve mentioned before this is where Arsenal’s squad are probably the weakest. Elneny is a great runner but he’s not a like for like replacement for Cazorla. He lacks the set-piece prowess of Cazorla, the dribbling (less than half as many this season), and the vision to pick out a teammate.

But more important than the stats is that Wenger has been inverting Cazorla and Coquelin in the Arsenal midfield. He’s told Coq to go play between the lines and win the ball higher up the pitch. Then he’s given Cazorla the responsibility with the ball in the deep pivot. Cazorla does this very well because he’s an excellent long passer, he’s made 20/25 long passes this season, and Cazorla is an excellent dribbler. Elneny was 65% long passing last season with 19/29 and is 1/2 this season and Elneny is much more likely to look for a back pass than to try to attack the opposition defense with a dribble.

Somehow, Arsenal need to be able to advance the ball with these two players this weekend (Xhaka is suspended) and that might prove difficult. Worse, any long-term injury to Cazorla will require a rethink to the Arsenal system because while Xhaka can and does pass the ball as well as Cazorla, he’s not as mobile as Elneny, and he’s not anywhere near the kind of dribbler that Cazorla is.

While I think this team is better than many of us gave it credit for early in the year I also think Middlesbrough is a bigger test than many believe. It’s a test of Arsenal in the air, can they apply pressure on the ball and give Negredo and company a hard time on long passes? And it’s a test of the Arsenal front four and whether they can drop and collect the ball, and then whether Iwobi and Walcott or Alexis and Ozil can fill in those spaces to create threats.

Qq

*Apologies if I mix up James Horncastle and Owen Gibson.