FairValue

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Portrait of Mario Hermoso

Mario

Hermoso

CBSpain · AS Roma

№ 281769Established €5.4M +0.26

Close-up

Image: FootyLogos

Player dossierSerie A

MarioHermoso

CBCentre-BackDefender

Club
AS Roma
League
Serie A
Nationality
Spain
Age
30
Height
184 cm
Foot
Left
Valued
29 May 2026

Reading the valuation

The market values Hermoso at €7M. Model A, which never saw Hermoso during training, estimates €5.4M: the market value is 30% above that estimate.

That is a factor of ×1.30. 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 €5M, 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.

▲ +0.26A €5.4M▲ +0.34B €5M
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
55
Minutes
3,670
Goals
5
Assists
2
Started
41/55
Min / app
67
Cards
14Y 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 Hermoso…

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 €7M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €7MModel A €5.4M

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

Mario Hermoso's percentiles among defenders: Goals per 90 92nd, Assists per 90 56th, Minutes, two years 64th, Starts 34th, Minutes, last 365 days 79th, European club minutes 89th92ndGoals56thAssists64thMinutes34thStarts79thRecent89thEurope

Dashed ring: the defender median (50th percentile)

Goals per 90

Club goals per 90 minutes played in the two years to the valuation date.

0.12 this player0.03 defender median92nd percentile

0.00peer deciles · median line · this player ●0.41

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
€200k
Mar 2014
Peak
€35M
Mar 2021
Model target
€7M
May 2026
Valuations
34
7 club changes
May 2026€7MAS RomaValuation the model is trained to reproduce

May 2026: €7M, AS Roma. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-03-07€200kReal Madrid U19
2015-07-17€200kReal Valladolid CF
2015-11-20€500kReal Valladolid CF
2016-02-22€500kReal Valladolid CF
2016-08-15€400kReal Madrid Castilla
2017-02-02€400kReal Madrid Castilla
2017-06-30€400kReal Madrid Castilla
2018-01-01€1.5MRCD Espanyol Barcelona
2018-05-30€5MRCD Espanyol Barcelona
2018-08-29€15MRCD Espanyol Barcelona
2018-10-31€20MRCD Espanyol Barcelona
2018-12-21€20MRCD Espanyol Barcelona
2019-06-11€25MRCD Espanyol Barcelona
2019-12-20€25MAtlético de Madrid
2020-04-08€20MAtlético de Madrid
2020-10-08€20MAtlético de Madrid
2020-11-23€25MAtlético de Madrid
2021-01-05€30MAtlético de Madrid
2021-03-19€35MAtlético de Madrid
2021-06-10€35MAtlético de Madrid
2021-12-30€30MAtlético de Madrid
2022-03-21€25MAtlético de Madrid
2022-06-03€20MAtlético de Madrid
2022-09-23€18MAtlético de Madrid
2022-11-07€14MAtlético de Madrid
2023-03-23€18MAtlético de Madrid
2023-06-13€20MAtlético de Madrid
2023-12-22€25MAtlético de Madrid
2024-06-07€25MAtlético de Madrid
2024-10-18€18MAS Roma
2024-12-18€10MAS Roma
2025-06-05€7MBayer 04 Leverkusen
2025-12-23€7MAS Roma
2026-05-29€7MAS Roma

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
+0.261

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 →

Serie A507 players · median €5.5M

Valued above 55% of the 507 Serie A players.

€100k€750k€5M€30M€7MSee them in the Explorer →

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

Valued above 76% of the 2,065 defenders.

€20k€200k€2M€20M€7MSee them in the Explorer →

Where Hermoso 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).