Players usually get to sign a new contract for one of two reasons:
1. Sustained increase in performance
2. Transferred to a new club
Both of these are two sides of the same coin where some kind of increased performance is rewarded either at the current club or by moving to a different club.
It’s an easy narrative to sell that a player whose contract is running down will put up good performances and try harder to secure that next payday. Whilst after they sign that contract they will try less hard as they have a secure future, and performances will drop.
Whilst that may be true in some specific cases, the integrity of the large majority of players surely wouldn’t be swayed that easily.
That’s what I’ve taken a look at here: how player performance in games leading up to their contract compared to their performance after signing the contract.
The players used were those with their contract dates available here: https://www.spotrac.com/epl/contracts/
They are the top 100 contracts from the English Premier League.
Whilst the player performance measures were taken from match logs on: https://fbref.com/
Player performance is not completely described in counting stats, no matter how advanced. Context is always necessary when interpreting statistics for football performances. This analysis will take a very high level view and take a rolling average of position specific measures in matches leading up to a contract date and then the same after to compare.
Even at this high level there is context to consider. Some of the contracts are due to increased performance levels whilst others are due to transfers which would likely be the result of increased performance.
For transfers, they can only occur in the transfer windows which are either January or in Summer. So some of these will be comparing between seasons and some will be comparing within seasons, but both will be playing with different players and potentially in different roles with their new teams.
For contract extensions in the same teams, they can occur at any time and so could occur mid-season.
Performance measures for positions are as you’d expect:
- For forwards they are mainly goalscoring measures
- Attacking midfielders are more creative measures
- Defensive midfielders are some possession and defensive measures
- Central defenders are similar to defensive midfielders actually
- Full backs are defensive measures and creativity.
So let’s take a look at some specific players. Below are a selection of high level players including Aubameyang, Kane, Grealish, De Bruyne, Chillwell, Wan Bisakka, Maguire. A mixture of transfers and extensions.
The first up is Aubameyang, who was the inspiration for this work. After signing a large extension with Arsenal it doesn’t feel like he’s hit the same levels as before, and the numbers suggest similar. Potentially guilty of the narrative not trying after securing the extension but more likely just a decline in performance due to age.
Next is Grealish, who has been amazing for Aston Villa, and potential transfer rumours to Man Utd. Though seems like his extension at Villa hasn’t had the same effect as Aubameyang. Arguably Grealish is even better now than before the contract. Potentially due to his age and motivation with the Euros coming up, the contract extension seems deserved.
Lastly is a transfer example with Ben Chilwell, had a great season with Leicester last year and now playing for a ‘better’ team at Chelsea. Though this whole process seems to have completely skipped Chillwell’s mind as his performances are as varied both before and after the transfer and new contract.
Now taking a look at whether contracts seem to affect some positions more than others. Each individual player’s average measure has been averaged to try to find an overall trend.
There are no clear drop offs after signing a new contract. Most of the time immediately before the contract seems to be the worst performances and they seem to pick it up afterwards. Perhaps contract talks have a negative effect on player performances from a mental perspective.
Arguably forwards have the sharpest drop in performance leading up to contracts, and whilst their performance does increase. It’s not certain they’ll return to pre-contract levels.
Forwards’ performance measures are largely affected by goalscoring, which is pretty lucky in itself. The players getting new contract and transfers are those that are likely to be performing well leading up to their contract or transfer. This likely includes some hot goalscoring streaks and over-performing which will be hard to replicate going forwards.
And finally taking a look at all positions together, to try to get an overall view at player performances before and after signing contracts.
It seems that there’s a drop in performance leading up to the contract and then it picks back up afterwards.
This is largely driven by the high pre-contract performances of forwards as discussed earlier. With the remaining positions not as large a difference.
As mentioned multiple times, this sample of players is implicitly biased towards players who have performed well before signing contracts, especially large ones. If looking at all contracts across all leagues and taking into account the contract monetary amount there may be further patterns to find.
But in this sample we seem to be seeing a slight drop in performance leading up to contracts and then a return to mostly similar levels afterwards. There is the inevitable regression to the mean argument which is applicable across all positions. It’s largely affecting positions and players that rely on more variable performance measures like goalscoring rather than midfielders or defenders whose measures include higher volume measures such as touches or passes.
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