FairValue

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Sergio

Herrera

GKSpain · CA Osasuna

№ 248738Established €2.2M +0.26

Player dossierLaLiga

SergioHerrera

GKGoalkeeperGoalkeeper

Club
CA Osasuna
League
LaLiga
Nationality
Spain
Age
33
Height
192 cm
Foot
Right
Valued
5 Jun 2026

Reading the valuation

The market values Herrera at €2.8M. Model A, which never saw Herrera during training, estimates €2.2M: the market value is 29% above that estimate.

That is a factor of ×1.29. 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 €3.1M, 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.

▲ +0.26A €2.2M▼ −0.11B €3.1M
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
76
Minutes
6,788
Started
76/76
Min / app
89
Cards
9Y 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 Herrera…

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 €2.8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €2.8MModel A €2.2M

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 485 goalkeepers

Sergio Herrera's percentiles among goalkeepers: Minutes, two years 91st, Starts 62nd, Minutes, last 365 days 87th, European club minutes 32nd91stMinutes62ndStarts87thRecent32ndEurope

Dashed ring: the goalkeeper median (50th percentile)

Minutes, two years

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

6,788 this player2,790 goalkeeper median91st percentile

450peer deciles · median line · this player ●9,210

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
€100k
Aug 2014
Peak
€8M
Jun 2022
Model target
€2.8M
Jun 2026
Valuations
26
2 club changes
Jun 2026€2.8MCA OsasunaValuation the model is trained to reproduce

Jun 2026: €2.8M, CA Osasuna. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-08-12€100kDeportivo Alavés B
2016-07-15€400kSD Huesca
2016-10-27€500kSD Huesca
2017-01-24€600kSD Huesca
2017-06-29€700kSD Huesca
2018-01-01€800kCA Osasuna
2018-05-30€800kCA Osasuna
2019-02-19€500kCA Osasuna
2019-06-29€500kCA Osasuna
2019-12-20€1.5MCA Osasuna
2020-04-08€1.2MCA Osasuna
2020-10-08€1.5MCA Osasuna
2021-01-05€1.8MCA Osasuna
2021-03-19€4MCA Osasuna
2021-06-10€6MCA Osasuna
2021-12-30€6MCA Osasuna
2022-06-03€8MCA Osasuna
2022-11-07€8MCA Osasuna
2023-06-13€8MCA Osasuna
2023-10-13€6MCA Osasuna
2023-12-22€6MCA Osasuna
2024-06-07€6MCA Osasuna
2024-12-27€4MCA Osasuna
2025-06-09€3MCA Osasuna
2025-12-12€3MCA Osasuna
2026-06-05€2.8MCA Osasuna

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
+0.256

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 39% of the 509 LaLiga players.

€100k€1M€10M€100M€2.8MSee them in the Explorer →

Goalkeepers, all leagues485 players · median €1M

Valued above 67% of the 485 goalkeepers.

€20k€200k€2M€20M€2.8MSee them in the Explorer →

Where Herrera 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).