CASE STUDY RESURGENCE OF XG IN LIGHT OF NEW CONTRACT: CHRISTIAN BENTEKE

I used to go up to KRC Genk a lot. It’s just a one hour drive from where I live and I have some great footballers and icons. Thomas Buffel. Jelle Vossen. Kevin de Bruyne. Thibaut Courtois. But the one that always stood by me, was Christian Benteke. I’ve always been fascinated by him and his career, so this is an excellent opportunity for me to write about him and his xG performances in the 2020/2021 season.

Benteke signed a two year contract extension just before Euro 2020 started, which will keep him a Palace player until the end of June 2023. He scored 10 goals in 30 league appearances, with a very strong finish – just before contract negotiations entered their final stages.

I want to see if there’s a relation between the end of the contract and the expected goals performance of a striker. Whether he is more motivated to show his skills in the light of a contract extension or attracting new clubs who he can sign for. Now, this is difficult to fully assess, because you cannot look in the mind of the player – but I will nonetheless try to attempt to look at his performances. I will look at the data from 2020/2021 with the difference between the first and second half of the season.

Data
The data has been retrieved from Wyscout and Instat at June 20th 2021. The players that are compared to Benteke, have played over 900 minutes and therefore the database consists of 65 players.

xG performance in 2020/2021

So, how well does Benteke do compared to his peers? In this scatterplot below we look at the shots per 90 vs the expected goals per 90 – because we want to look at the chances and how big the chances were. This gives an idea of the probability of scoring and whether Benteke is a top performer in the 2020/2021 Premier League season.

As you can see in the scatterplot above, Benteke still is really present in both shots per 90 and xG per 90 in the Premier League. He has 3,09 shots per 90 in this season with only Salah, Kane and Jota shooting more per 90 minutes than the Belgium. When we look at xG per 90, Benteke has 0,54 xG per 90 minutes. Only Vardy, Salah, Bamford, Antonio, Kane and Jota have a higher xG per 90 minutes than Benteke.

As we can see Benteke is one of the best performers in the metrics we analysed above, but how well does he do overall per game this season? To see if he actually had a better xG per game in the latter stages of the season, we need to look at what he performed per game. In the graph below you see the xG per matchday. Important is that these matchdays are all of Benteke’s matchdays and not the official matchdays of the Premier League.

We can see a few interesting things about Benteke’s xG performance in this season. We see that he had a difficult start with four games without xG, but they were also games where he didn’t play many minutes. He has two big xG games, before gradually going down in matchday 14, 19 and 23. Before matchday 24 he fails to grow his xG, but from matchday 24 – he is on the rise again, resulting in the highest xG of the season in matchday 28. This tells us that he finished really strongly, but there are a few questions that arise.

What kind of chances were there in those games? Did he take many chances that were lower xG or just a few high xG chances? In the graph below you can see the volume of shots in every game and the corresponding xG that comes with it.

So, when look at this particular graph we don’t see any big differences from the xG graph – but another thing that is worth looking at is the volume of shots released. The change in consistency of shots taken from matchday 24 is an upgrade from before and in these last 6 games he has had 3 shots or more in each of those games. With consistently shooting, Benteke also upped his xG in these final games of the season.

Shotmaps

Above you can see the shot map of Benteke in this current season with the size of the dots representing the size of the expected goals. This gives an idea of the total shots per season, and from where he attempted his shots. The goals are indicated in red, the shots are indicated in grey. In general, the closer you get to the goal, the higher the xG is.

In the shotmap below you can see the shotmap of the last six games and see whether his xG comes from volume or that it comes from high quality chances that are taken.

What we can conclude from the shot map above is that Benteke has tried to shoot a lot from inside the penalty area. He had 22 shots of which 4 were goals with an xG of of 5,22. So if anything, he was slightly underperforming his xG – but he was getting in the right positions to make more goals.

All this has to do with the way Crystal Palace plays, the momentum they have, how well Benteke’s team mates are doing and the opposition, but the fact remains that the expected goals in the last six game have significantly become higher.

Final thoughts
It’s difficult to draw a conclusion from the data illustrated above and the thought of contract negotiations. But we can see a few things. First of all we can see that the xG number has become bigger to the end of the season. Earlier in the season there were big numbers, but also quite low points. In the end of the season this isn’t the case anymore.

Secondly, the volume of shots has not only risen, but has been quite consistent. Consistently shooting more than three times per 90 minutes in the final six games of the season, has definitely added to the xG. Added to that is that four of the ten goals scored by Benteke, have come in that final six games of the season – where he also made sure that he was in the penalty area a lot.

Again, it’s difficult to draw a line and say that his intention of playing direct, more efficiently has a direct correlation with a new contract, but it would be a very big coincidence if the increase in xG would just happen at the end of the season.

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