Christos Tzolis: The Debrief

Getting the low-down on Arsenal's newest signing

Arsenal have completed their second signing of the summer, bringing in Christos Tzolis for £34m from Club Brugge.

The reception to the news was a bit colder than I would have hoped but that is probably more of a reflection of the ordering of when deals will be completed this season. As fans we want to see the big stars signed, and even with his incredible numbers, Tzolis is not that.

If I believed that this was it for the business, I could understand the frustration but I don’t think that this will be it for Arsenal in the attacking portion of the pitch so I am able to put that into context and hopefully that will be the case for most people, especially as the rest of the summer goes on.

As is tradition, let’s go through the numbers for the player and what the club is signing.

If you want the DEEP dive into him I have done that here:

Christos Tzolis: The Debrief

One of the stories that has accompanied this signing is that he was a data driven pick and just looking at the graphics above that makes a ton of sense. He has put up crazy, video game type numbers that would put him in rare company if you include the Belgian League in the stats rankings last season.

The big question surrounding him would be how does all of that translate with a move to the Premier League. We will touch on that at the end. Until then, the stats below are for his domestic league production last season and are normalized to per 90 minutes, they are compared against other wingers with at least 900 minutes played in the top five leagues going back to the 2011-12 season.

Attacking and Creative Metrics:

0.41 - Non-Penalty Goals, percentile: 91.9

0.44 - Non-Penalty xG, percentile: 97.1

3.34 - Open Play Shots, percentile: 98.5

0.13 - xG Per Shot, percentile: 81.2

-0.05 - Post Shot xG Added (The difference in xG of a shot and the estimated finishing quality Post Shot xG), percentile: 7.6

35.8 - On Target Percentage, percentile: 49.1

0.53 - Set Play Shots, percentile: 76.5

20.6% - Shot Usage (the percentage of total shots while playing that the player attempted), percentile: 82.8

23.9% - xG Usage (the percentage of total xG while playing that the player took the shot from), percentile: 87.9

I wouldn’t call Tzolis’s shooting his greatest strength but last season he still put up very good shooting numbers in the Belgian League. Here were his per 90 ranks last season, 6th in shots, 10th in non-pen xG, and 10th in non-pen goals. Those are good ranks for a wide player, I wouldn’t expect him to be an elite goal scorer but he showed good ability to find the back of the net.

Last season he didn’t have a great shot placement season but he was about average for his shooting accuracy. He rates out as a pretty close to average finisher for his career so it is possible that this is just noise but something that could be a drag on the goal scoring if it continues.

Now into the creative numbers.

0.67 - Assists, percentile: 99.9

0.61 - Shot Assisted xA, percentile: 99.9

3.90 - Key Passes, percentile: 99.9

7.05 - Shot Creating Actions, percentile: 99.5

1.00 - Shot Creating Action xG Assisted, percentile: 99.1

4.49 - Shot Zone Pass Completions, percentile: 100

29.8% - Key Pass Usage, percentile: 97.5

This is where he goes from good to WOW.

Even if you discount heavily for the league that he played in, he was one of the most prolific creative players in any league last season. I fully expect the numbers to drop with a move to the Premier League but they are dropping from such a high baseline that even a pretty large drop keeps him in the very good range.

Passing and Ball Progression Metrics:

99% - Pass Efficiency (actual passing completion divided by the expected completion percentage), percentile: 82.4

0.25 - Goal Probability Added through Passing (Measure of changes in the teams chances of scoring/conceding following pass attempts), percentile: 99.8

48.9 - Passing Volume (total attempts), percentile: 89.7

71.4% - Pass Completion Percentage, percentile: 46.8

2.30 - Completed Final Third Entries, percentile: 60.5

5.28 - Progressive Passes Completed, percentile: 96.0

262.3 - Progressive Passing Distance, percentile: 90.4

23.6 - Attacking 3rd Pass Attempts, percentile: 97.6

72.3% - Attacking 3rd Pass Completion Percentage, percentile: 58.9

102.1% - Attacking 3rd Pass Efficiency

2.21 - Long Pass Attempts, percentile: 91.6

59.2% - Long Pass Completion Percentage, percentile: 51.0

Like his creative numbers, his passing is a strength. He’s not breaking the scale here but he does show up quite well, especially for his ability around the final third.

One thing that also really pops here is his total involvement in positive possessions. He isn’t just a final product player and does quite a bit of work to add value all around the attacking half of the pitch.

1.72 - xG Chain (total xG involved in), percentile: 99.1

1.04 - xG Buildup (total xG involved in, excluding the shot and key pass), percentile: 96.7

45.4% - xG Buildup Usage (the percentage of total xG while on the field that he participated in the buildup to), percentile: 95.5

14.8 - Shot involvement (Buildup + Key Pass + Shot Taken), percentile 99.3

Carrying, Dribbles, and Receiving Metrics:

9.21 - Progressive Carries, percentile: 97.1

0.19 - Goal Probability Added through Carrying/Dribbles (Measure of changes in the team’s chances of scoring/conceding following carries and attacking duel attempts), percentile: 92.4

3.32 - Carries into the attacking third, percentile: 88.1

3.18 - Carries into the box, percentile: 98.4

2.74 - Dribbles Attempted, percentile: 31.4

1.17 - Dribbles Completed, percentile: 35.1

42.6% - Dribble Success %, percentile: 50.4

0.96 - Dispossessed, percentile: 87.0

1.72 - Foul Suffered, percentile: 61.8

Tzolis has good ball carrying numbers but he isn’t a “dribbly” winger in my mind. He completed 40 dribbles last season in the Pro League, which was good enough for 13th best but on a per 90 basis he drops out of the top 25. He was top for progressive carries (2nd per 90) so he will drive into space that is available but he isn’t exactly going to use speed or trickery to eliminate defenders or create chaos.

He is a high volume player and when combined with his ability to move with the ball at his feet, he finds himself in lots of dangerous locations.

69.5 - Touches per 90, percentile: 90.8

39.8 - Final third touches, percentile: 97.3

8.37 - Touches in the box, percentile: 98.6

11.1 - Deep Touches (within 25 yards of goal), percentile: 98.2

4.61 - Shot Zone Touches, percentile: 98.4

43.3 - Passes Received, percentile: 99.2

8.98 - Progressive Passes Received, percentile: 99.2

10.6 - Final Third Entry Received, percentile: 96.8

3.21 - Penalty Area Passes Received, percentile: 96.2

0.32 - Crosses Received, percentile: 41.0

1.17 - Miscontrolled passes, percentile: 36.9

2.7% - Miscontrolled pass %, percentile: 62.2

Overall, the numbers look good here. He was able to get more central touches than the typical Arsenal left winger but he is still comfortable playing out near the touchline and receiving after getting chalk on his boots.

Ball Winning Metrics:

4.77 - Possession Adjusted (padj) Defensive Duels Contested, percentile: 47.6

1.00 - Padj Successful Tackles, percentile: 21.6

0.53 - Padj Dribbled Past, percentile: 82.2

31.5% - Tackle % (Successful Tackles/ Tackles + Fouls Committed), percentile: 12.4

19.6% - Dribbled Past % (Dribbled Past/ Tackles Attempted), percentile: 84.2

1.2 - Padj Clearances, percentile: 83.8

1.1 - Padj Fouls Committed, percentile: 55.8

0.38 - Padj Interceptions, percentile: 14.5

0.72 - Padj blocked passes, percentile: 35.6

4.53 - Padj Ball Recoveries, percentile: 48.9

1.51 - Padj Second balls won, percentile: 52.7

The ball winning numbers look respectable here. He was the talisman for Brugge and that can often mean a player doesn’t need to put in a major shift defensively but Tzolis was still there putting in the effort on the wing. That is one of the non-negotiables for Arteta and the current evidence suggests it won't be a problem for Tzolis.

Final thoughts

We have waited long enough and we can’t go any further without looking at the league strength question with Tzolis.

I do believe that the reputation of the Belgian League and the reality might be out of sync but there is no denying that it is significantly weaker than the Premier League. On my implementation of Elo ratings, Belgium ranks as the 6th strongest league in Europe, stronger than the Eredivisie and the Portuguese league.

It doesn’t have the same elite team talents but the bottom of the League is still quite strong overall.

The Belgian league also splits its season into two phases (at least it did through last season). After a standard double round robin, the league divides into tiers and you play the top teams again. That gave him more matches against the best sides than a normal calendar would. Even with this, there is still just no getting around that most of the matches that he played last season were against teams around the bottom of the Premier League level.

To account for this you would probably want to knock off about a third of the production here. When you do that, because he was such an outlier you still end up looking at a player that put up strong numbers overall.

If you want to limit the opposition to matches where he played against teams that were rated as Premier League quality or better and expand to the Champions League you do get a decent sample size of 15.1 nineties and numbers that take a hit, but still show up looking quite good.

None of this is a guarantee that this will work but it is reassuring to see that his production still holds up when you try to account for this.

I am excited for this player. I think that it is the right type of bet on the player profile and it is in the right price range to be comfortable. He's exactly the type of player a Brighton, Brentford, or Bournemouth signs for this price and flips for double or triple the fee a season later, after he's proven it translates at the Premier League level. It would be nice to cut out the middleman for once and keep the upside ourselves.

Welcome, Christos.