FairValue

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Lilian

Brassier

CBFrance · Stade Rennais FC

№ 485960Elite €9.8M +0.20

Player dossierLigue 1

LilianBrassier

CBCentre-BackDefender

Club
Stade Rennais FC
League
Ligue 1
Nationality
France
Age
26
Height
186 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Brassier at €12M. Model A, which never saw Brassier during training, estimates €9.8M: the market value is 23% above that estimate.

That is a factor of ×1.23. 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 €2M, 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.

▲ +0.20A €9.8M▲ +1.78B €2M
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
53
Minutes
4,268
Goals
1
Assists
2
Started
48/53
Min / app
81
Cards
6Y 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 Brassier…

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 €12M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €12MModel A €9.8M

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

Lilian Brassier's percentiles among defenders: Goals per 90 41st, Assists per 90 52nd, Minutes, two years 74th, Starts 71st, Minutes, last 365 days 69th, European club minutes 30th41stGoals52ndAssists74thMinutes71stStarts69thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

4,268 this player2,860 defender median74th 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
€500k
Sept 2019
Peak
€12M
Jun 2024
Model target
€12M
Jun 2026
Valuations
22
4 club changes
Jun 2026€12MStade Rennais FCValuation the model is trained to reproduce

Jun 2026: €12M, Stade Rennais FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-09-30€500kValenciennes FC
2020-01-06€700kValenciennes FC
2020-04-08€625kValenciennes FC
2020-08-03€1.5MStade Rennais FC
2020-10-15€1.5MStade Brestois 29
2021-01-07€2MStade Brestois 29
2021-04-09€2.5MStade Brestois 29
2021-06-04€2.5MStade Brestois 29
2021-10-08€3MStade Brestois 29
2021-12-16€3MStade Brestois 29
2022-05-30€4MStade Brestois 29
2022-11-02€4MStade Brestois 29
2023-06-27€5MStade Brestois 29
2023-10-16€7MStade Brestois 29
2023-12-18€8MStade Brestois 29
2024-03-19€10MStade Brestois 29
2024-06-03€12MStade Brestois 29
2024-12-10€10MOlympique Marseille
2025-06-03€10MStade Rennais FC
2025-12-15€10MStade Rennais FC
2026-03-27€12MStade Rennais FC
2026-06-01€12MStade Rennais 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
+0.204

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 →

Ligue 1423 players · median €5M

Valued above 72% of the 423 Ligue 1 players.

€100k€750k€5M€30M€12MSee them in the Explorer →

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

Valued above 84% of the 2,065 defenders.

€20k€200k€2M€20M€12MSee them in the Explorer →

Where Brassier 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).