I used data to help find a improvements in the leaky Arsenal back line

Finding a new centre-back for Arsenal. A Thread:

In order to recommend defenders, we need to first establish what makes a good defender.

This is quite subjective as most stats to measure defensive output don't take into account whether the player was out of position before making (for example) a tackle, in the first place.

A potential place to start would be to look at what metrics the "best" defenders excel in.

Below is Van Dijk's 18/19 POTY season in numbers.

- 93% of dribblers tackled
- 0 errors leading to shots
- 71% Tackle win rate
- 81% Aerial win rate

Incredible stat line.

Along with these stats Van Dijk is 6'4, fast, strong and possessed great co-ordination for his body type, along with ability on the ball, which will be discussed later.

Any club looking for an effective centre-back should ideally look for a similar profile.

Not many, including Van Dijk himself, will ever touch these stats for a long time but taking them into account a optimistic filter to start for a new centre-back could be:

- 50% of dribblers tackled
- 60% Tackle win rate
- 67% Aerial win rate

If we filter for U24 centre backs based on the criteria we set, 9 names are found int the top 5 leagues. Some well known players there being:

- Ozan Kabak
- Gabriel
- Mohammed Salisu

The likes of Pau Torres and Tapsoba very narrowly miss out.

But Van Dijk didn't just excel defensively, he was also very useful when progressing the ball, in 18/19 Van Dijk had:

- 614 metres progressed by passing per game
- 4.84 passes into the final 3rd
- 90% pass completion
- 86% long pass completion

Elite numbers.

Taking this into account, a potential filter to search for a centre-back could be:

- 350 metres progressed by passing per 90
- 2.4 passes into the final 3rd per 90
- 85% pass completion
- 75% long pass completion

If we look for U24 centre backs based on the criteria we set, it narrows down the previous 9 names to:
- Ozan Kabak
- Nikola Milenković
- Gabriel
- Duje Ćaleta-Car

An issue with Arsenal CB's in recent times is their rashness a trait that our previous example, Van Dijk doesn't show.

Ordering the 4 names based on least fouls p90 we get:

1. Gabriel (0.96)
2. Ozan Kabak (1.14)
3. Duje Ćaleta-Car (1.29)
4. Nikola Milenković (1.44)

With Saliba being right footed it would also be preferred that the other CB would be left-footed to play on the left side. Below are the four, ranked on the percentage of times they use their left foot:

1. Gabriel 93%
2. Ćaleta-Car 30%
3. Ozan Kabak 12%
4. Milenković 12%

Physically, It would be ideal for a CB to be fast, yet strong, whilst still mobile. This is very hard to measure through stats but from watching them, none of them suffer in any of the aspects. I noticed Gabriel to be particularly powerful when challenging for the ball.

And finally, although this doesn't account for off-ball errors (ie losing a runner), below shows the defenders ranked on how often they made errors leading to shots this season:

- Gabriel 0 in 23.2 90's
- Kabak 0 in 18.2 90's
- Milenkovic 1 in 25 90's
- Caleta-Car 1 in 21 90's

RANKINGS:

Honourable mention: Pau Torres

Pau Torres is phenomenal at tackling on the ground, athletic, left-footed, and has experience playing out from the back at Villereal, however he is average in the air. but at 22, there is still a lot of time to improve.

Honourable mention: Mohammed Salisu

Almost making it into the 4 man shortlist, Mohammed Salisu was impressive in almost all the criteria. However even relative to his teammates at Validoid, he struggled at progressing the play, a great prospect nonetheless.

3rd Place: Duje Ćaleta-Car

At 22, Caleta-Car already has experience playing for one of France's biggest clubs and does well in most of the metrics we used today. a promising player who will, unfortunately for Arsenal, attract a large fee.

2nd Place: Ozan Kabak

The youngest player on the initial 9-man shortlist, Ozan Kabak being 20 and producing such quality output is incredible, he has almost no weaknesses on paper but may need more experience, as the step over to the Premier League is not a small one.

1st Place: Gabriel

Excelling in almost every metric, Gabriel combines defensive proficiency with physicality. He also has experience playing out from the back in a high line, makes few errors, is left-footed, and can even speak languages of most of the squad. A perfect fit.

Thanks for reading

RT's and likes appreciated