FairValue

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Portrait of Santiago Castro

Santiago

Castro

CFArgentina · Bologna FC 1909

№ 849520World Class €52.7M −0.50

Close-up

Image: FootyLogos

Player dossierSerie A

SantiagoCastro

CFCentre-ForwardAttack

Club
Bologna FC 1909
League
Serie A
Nationality
Argentina
Age
21
Height
179 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Castro at €32M. Model A, which never saw Castro during training, estimates €52.7M: the market value is 39% below that estimate.

That is a factor of ×1.65. Model A's typical held-out miss is ×1.50 either way, so this gap is larger than its usual error.

Without league and club, Model B estimates €40.3M, 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.

▼ −0.50A €52.7M▼ −0.23B €40.3M
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
97
Minutes
6,263
Goals
21
Assists
12
Started
73/97
Min / app
65
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 Castro…

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 €32M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €32MModel A €52.7M

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 1,583 attackers

Santiago Castro's percentiles among attackers: Goals per 90 58th, Assists per 90 60th, Minutes, two years 98th, Starts 76th, Minutes, last 365 days 98th, European club minutes 81st58thGoals60thAssists98thMinutes76thStarts98thRecent81stEurope

Dashed ring: the attacker median (50th percentile)

Minutes, last 365 days

Club minutes in the final year of the window: recent involvement, or the absence of it.

3,443 this player1,301 attacker median98th percentile

0peer deciles · median line · this player ●4,703

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
May 2022
Peak
€35M
Mar 2025
Model target
€32M
May 2026
Valuations
13
1 club change
May 2026€32MBologna FC 1909Valuation the model is trained to reproduce

May 2026: €32M, Bologna FC 1909. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2022-05-24€100kCA Vélez Sarsfield
2022-10-26€1MCA Vélez Sarsfield
2023-07-04€1MCA Vélez Sarsfield
2023-10-04€3.5MCA Vélez Sarsfield
2023-12-19€7MCA Vélez Sarsfield
2024-03-12€12MBologna FC 1909
2024-06-05€12MBologna FC 1909
2024-10-18€18MBologna FC 1909
2024-12-18€25MBologna FC 1909
2025-03-25€35MBologna FC 1909
2025-06-17€35MBologna FC 1909
2025-12-23€35MBologna FC 1909
2026-05-29€32MBologna FC 1909

Audit context group-level, not about this player

Audit group
non-UEFA
Population gap, Model A
+0.093 95% CI +0.063 to +0.124
This player, market vs held-out A
−0.499

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 94% of the 507 Serie A players.

€100k€750k€5M€30M€32MSee them in the Explorer →

Attackers, all leagues1,583 players · median €2.5M

Valued above 94% of the 1,583 attackers.

€20k€300k€5M€75M€32MSee them in the Explorer →

Where Castro 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).