FairValue

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Portrait of Zeno Debast

Zeno

Debast

CBBelgium · Sporting CP

№ 548193Elite €11.9M +0.86

Image: FootyLogos

Player dossierLiga Portugal

ZenoDebast

CBCentre-BackDefender

Club
Sporting CP
League
Liga Portugal
Nationality
Belgium
Age
22
Height
191 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Debast at €28M. Model A, which never saw Debast during training, estimates €11.9M: the market value is 136% above that estimate.

That is a factor of ×2.36. 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 €12.4M, closer to the market here, although it is usually further off (typical miss ×2.07).

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

▲ +0.86A €11.9M▲ +0.81B €12.4M
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
64
Minutes
4,215
Goals
1
Assists
6
Started
44/64
Min / app
66
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 Debast…

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 €28M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €28MModel A €11.9M

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

Zeno Debast's percentiles among defenders: Goals per 90 42nd, Assists per 90 84th, Minutes, two years 73rd, Starts 25th, Minutes, last 365 days 40th, European club minutes 82nd42ndGoals84thAssists73rdMinutes25thStarts40thRecent82ndEurope

Dashed ring: the defender median (50th percentile)

Assists per 90

Club assists per 90 minutes in the same window.

0.13 this player0.04 defender median84th percentile

0.00peer deciles · median line · this player ●0.58

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
€400k
Mar 2021
Peak
€30M
May 2025
Model target
€28M
May 2026
Valuations
18
2 club changes
May 2026€28MSporting CPValuation the model is trained to reproduce

May 2026: €28M, Sporting CP. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2021-03-17€400kRSC Anderlecht U21
2021-06-07€800kRSC Anderlecht U21
2022-01-06€800kRSC Anderlecht
2022-04-12€2MRSC Anderlecht
2022-09-07€4MRSC Anderlecht
2022-11-04€8MRSC Anderlecht
2023-03-22€10MRSC Anderlecht
2023-06-09€10MRSC Anderlecht
2023-10-23€13MRSC Anderlecht
2023-12-19€13MRSC Anderlecht
2024-03-22€15MRSC Anderlecht
2024-06-04€18MRSC Anderlecht
2024-10-08€22MSporting CP
2024-12-19€24MSporting CP
2025-03-31€26MSporting CP
2025-05-30€30MSporting CP
2025-12-18€30MSporting CP
2026-05-28€28MSporting CP

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
+0.858

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 →

Liga Portugal423 players · median €1M

Valued above 96% of the 423 Liga Portugal players.

€20k€200k€2M€20M€28MSee them in the Explorer →

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

Valued above 95% of the 2,065 defenders.

€20k€200k€2M€20M€28MSee them in the Explorer →

Where Debast 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).