FairValue

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Portrait of William Saliba

William

Saliba

CBFrance · Arsenal FC

№ 495666World Class €74.1M +0.30

Image: FootyLogos

Player dossierPremier League

WilliamSaliba

CBCentre-BackDefender

Club
Arsenal FC
League
Premier League
Nationality
France
Age
25
Height
192 cm
Foot
Right
Valued
3 Jun 2026

Reading the valuation

The market values Saliba at €100M. Model A, which never saw Saliba during training, estimates €74.1M: the market value is 35% above that estimate.

That is a factor of ×1.35. Model A's typical held-out miss is ×1.50 either way, so this gap is within its usual error.

Without league and club, Model B estimates €43.6M, 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.

▲ +0.30A €74.1M▲ +0.83B €43.6M
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
96
Minutes
8,285
Goals
3
Assists
1
Started
94/96
Min / app
86
Cards
5Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Saliba…

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 €100M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €100MModel A €74.1M

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

William Saliba's percentiles among defenders: Goals per 90 51st, Assists per 90 34th, Minutes, two years 100th, Starts 92nd, Minutes, last 365 days 99th, European club minutes 89th51stGoals34thAssists100thMinutes92ndStarts99thRecent89thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

8,285 this player2,860 defender median100th 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
€3M
Oct 2018
Peak
€100M
Jun 2026
Model target
€100M
Jun 2026
Valuations
23
4 club changes
Jun 2026€100MArsenal FCValuation the model is trained to reproduce

Jun 2026: €100M, Arsenal FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2018-10-24€3MAS Saint-Étienne
2018-12-17€3MAS Saint-Étienne
2019-06-03€12MAS Saint-Étienne
2019-09-27€25MAS Saint-Étienne
2019-12-19€25MAS Saint-Étienne
2020-04-08€22.5MAS Saint-Étienne
2020-10-13€22.5MArsenal FC
2020-12-17€17MArsenal FC
2021-06-04€18MOGC Nice
2021-12-16€24MOlympique Marseille
2022-05-30€30MOlympique Marseille
2022-09-15€40MArsenal FC
2022-11-03€50MArsenal FC
2023-03-16€55MArsenal FC
2023-06-20€65MArsenal FC
2023-10-09€70MArsenal FC
2023-12-19€75MArsenal FC
2024-03-14€80MArsenal FC
2024-05-27€80MArsenal FC
2024-12-16€80MArsenal FC
2025-05-30€80MArsenal FC
2025-12-09€90MArsenal FC
2026-06-03€100MArsenal FC

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
+0.300

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 →

Premier League555 players · median €18M

Joint 4th highest observed value among 555 Premier League players.

€150k€1M€7.5M€50M€100MSee them in the Explorer →

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

The highest observed value among 2,065 defenders.

€20k€200k€2M€20M€100MSee them in the Explorer →

Where Saliba 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).