FairValue

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Mats

Deijl

RBNetherlands · Feyenoord Rotterdam

№ 369554Established €7.6M −1.34

Player dossierEredivisie

MatsDeijl

RBRight-BackDefender

Club
Feyenoord Rotterdam
League
Eredivisie
Nationality
Netherlands
Age
28
Height
181 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Deijl at €2M. Model A, which never saw Deijl during training, estimates €7.6M: the market value is 74% below that estimate.

That is a factor of ×3.80. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €11M, further from the market. Model B is usually further off (typical miss ×2.07): league and club explain much of how the market prices players.

A gap describes the model's arithmetic for this player's inputs, not what the player is worth.

▼ −1.34A €7.6M▼ −1.70B €11M
Pitch length is a log value scale fitted to this player's figures. ● observed · ◇ Model A · dashed ◇ Model B · each arc is a residual, log(observed) − log(estimate).
Apps
83
Minutes
7,401
Goals
8
Assists
6
Started
82/83
Min / app
89
Cards
8Y 0R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Deijl…

SHAP describes the model's arithmetic for this player's inputs, not what causes market value. Model B can be explained only by the live service; Model A also has a published explanation for the research players.

Model A vs Model B against the observed €2M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2MModel A €7.6M

Asking the prediction API…

Held-out estimates come from cross-validation, with this player outside the training data: the honest comparison. Served models were refitted on every player, this one included, so they sit closer to the market. Shaded band: Model A's typical miss (×1.50 either way).

Player traitspercentiles vs 2,065 defenders

Mats Deijl's percentiles among defenders: Goals per 90 86th, Assists per 90 69th, Minutes, two years 99th, Starts 94th, Minutes, last 365 days 97th, European club minutes 73rd86thGoals69thAssists99thMinutes94thStarts97thRecent73rdEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

Total club minutes in the two-year window: how much the player was used.

7,401 this player2,860 defender median99th percentile

451peer deciles · median line · this player ●9,111

No passing, progression or defensive actions exist in the dataset, so no trait claims to measure them.

Valuation history every Transfermarkt valuation on record

First valuation
€25k
Apr 2015
Peak
€2M
May 2025
Model target
€2M
May 2026
Valuations
23
4 club changes
May 2026€2MFeyenoord RotterdamValuation the model is trained to reproduce

May 2026: €2M, Feyenoord Rotterdam. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-04-12€25kBrabant United U19
2015-07-01€25kBrabant United U21
2016-02-05€25kBrabant United U21
2017-02-02€25kFC Den Bosch
2017-06-21€50kFC Den Bosch
2018-03-01€100kFC Den Bosch
2018-06-29€175kFC Den Bosch
2019-01-21€175kFC Den Bosch
2019-07-03€175kFC Den Bosch
2020-06-29€250kFC Den Bosch
2020-12-31€250kFC Den Bosch
2022-01-05€350kGo Ahead Eagles
2022-06-08€425kGo Ahead Eagles
2022-11-11€500kGo Ahead Eagles
2023-06-23€700kGo Ahead Eagles
2023-12-15€900kGo Ahead Eagles
2024-03-18€1.2MGo Ahead Eagles
2024-05-31€1.2MGo Ahead Eagles
2024-10-14€1.5MGo Ahead Eagles
2024-12-17€1.5MGo Ahead Eagles
2025-05-28€2MGo Ahead Eagles
2025-12-02€2MGo Ahead Eagles
2026-05-28€2MFeyenoord Rotterdam

Audit context group-level, not about this player

Audit group
UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−1.335

The group comes from first-listed citizenship and is never a model input. Across the population, non-UEFA players' market values sit about 10% above Model A's held-out estimates, relative to UEFA players in the same leagues. One player's residual says nothing about that pattern (typical miss ×1.50), and none of it is evidence of discrimination: the target may itself be biased. Open the Fairness Audit

In context observed value among comparable players in this build

All players in the Terminal →

Eredivisie425 players · median €1M

Valued above 62% of the 425 Eredivisie players.

€75k€500k€3M€20M€2MSee them in the Explorer →

Defenders, all leagues2,065 players · median €2M

Valued above 49% of the 2,065 defenders.

€20k€200k€2M€20M€2MSee them in the Explorer →

Where Deijl appears

Watchlists and the comparison tray are kept in this browser only.

Near this valuation closest observed values: same league, then same position

Counts and ranks of observed Transfermarkt values only; model errors are never ranked here. Full player export: Every player in the modelling population (D-011).