FairValue

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Ferland

Mendy

LBFrance · Real Madrid

№ 291417Established €5.2M −0.27

Player dossierLaLiga

FerlandMendy

LBLeft-BackDefender

Club
Real Madrid
League
LaLiga
Nationality
France
Age
30
Height
180 cm
Foot
Left
Valued
5 Jun 2026

Reading the valuation

The market values Mendy at €4M. Model A, which never saw Mendy during training, estimates €5.2M: the market value is 23% below that estimate.

That is a factor of ×1.31. 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 €1.3M, 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.

▼ −0.27A €5.2M▲ +1.09B €1.3M
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
40
Minutes
2,697
Goals
0
Assists
2
Started
34/40
Min / app
67
Cards
2Y 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 Mendy…

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 €4M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €4MModel A €5.2M

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

Ferland Mendy's percentiles among defenders: Goals per 90 18th, Assists per 90 66th, Minutes, two years 47th, Starts 56th, Minutes, last 365 days 10th, European club minutes 99th18thGoals66thAssists47thMinutes56thStarts10thRecent99thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

45% this player0% defender median99th percentile

0%peer deciles · median line · this player ●85%

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
€150k
Sept 2015
Peak
€50M
Mar 2021
Model target
€4M
Jun 2026
Valuations
34
2 club changes
Jun 2026€4MReal MadridValuation the model is trained to reproduce

Jun 2026: €4M, Real Madrid. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2015-09-06€150kLe Havre AC
2016-02-04€250kLe Havre AC
2016-07-13€300kLe Havre AC
2017-03-20€700kLe Havre AC
2017-06-15€1.3MLe Havre AC
2017-10-12€4MOlympique Lyon
2018-01-24€7MOlympique Lyon
2018-06-04€12MOlympique Lyon
2018-12-17€12MOlympique Lyon
2019-03-07€30MOlympique Lyon
2019-06-03€30MOlympique Lyon
2019-09-10€40MReal Madrid
2019-12-20€35MReal Madrid
2020-03-05€40MReal Madrid
2020-04-08€32MReal Madrid
2020-07-23€40MReal Madrid
2020-10-08€40MReal Madrid
2021-01-05€40MReal Madrid
2021-03-19€50MReal Madrid
2021-06-10€50MReal Madrid
2021-12-30€50MReal Madrid
2022-06-03€40MReal Madrid
2022-11-07€40MReal Madrid
2023-03-23€35MReal Madrid
2023-06-13€25MReal Madrid
2023-10-13€20MReal Madrid
2023-12-22€20MReal Madrid
2024-06-07€22MReal Madrid
2024-12-27€18MReal Madrid
2025-06-09€14MReal Madrid
2025-10-02€10MReal Madrid
2025-12-12€8MReal Madrid
2026-03-16€6MReal Madrid
2026-06-05€4MReal Madrid

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
−0.267

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 →

LaLiga509 players · median €4M

Valued above 50% of the 509 LaLiga players.

€100k€1M€10M€100M€4MSee them in the Explorer →

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

Valued above 65% of the 2,065 defenders.

€20k€200k€2M€20M€4MSee them in the Explorer →

Where Mendy 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).