FairValue

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Romain Del

Castillo

RWFrance · Stade Brestois 29

№ 353399Established €5.8M +0.18

Player dossierLigue 1

Romain DelCastillo

RWRight WingerAttack

Club
Stade Brestois 29
League
Ligue 1
Nationality
France
Age
30
Height
172 cm
Foot
Left
Valued
1 Jun 2026

Reading the valuation

The market values Castillo at €7M. Model A, which never saw Castillo during training, estimates €5.8M: the market value is 20% above that estimate.

That is a factor of ×1.20. 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 €5.1M, 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.

▲ +0.18A €5.8M▲ +0.31B €5.1M
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
65
Minutes
4,221
Goals
15
Assists
7
Started
49/65
Min / app
65
Cards
3Y 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 Castillo…

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 €5.8M

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 1,583 attackers

Romain Del Castillo's percentiles among attackers: Goals per 90 60th, Assists per 90 51st, Minutes, two years 83rd, Starts 76th, Minutes, last 365 days 90th, European club minutes 67th60thGoals51stAssists83rdMinutes76thStarts90thRecent67thEurope

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.

2,646 this player1,301 attacker median90th 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
€150k
Feb 2016
Peak
€10M
Jun 2024
Model target
€7M
Jun 2026
Valuations
28
4 club changes
Jun 2026€7MStade Brestois 29Valuation the model is trained to reproduce

Jun 2026: €7M, Stade Brestois 29. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-02-04€150kOlympique Lyon B
2016-07-13€150kFootball Bourg-en-Bresse Péronnas 01
2017-03-20€600kFootball Bourg-en-Bresse Péronnas 01
2017-06-15€800kFootball Bourg-en-Bresse Péronnas 01
2018-05-16€1.5MNîmes Olympique
2018-09-06€2.5MStade Rennais FC
2018-12-17€2.5MStade Rennais FC
2019-06-03€3.5MStade Rennais FC
2019-12-19€5MStade Rennais FC
2020-03-13€6MStade Rennais FC
2020-04-08€4.8MStade Rennais FC
2020-10-15€6MStade Rennais FC
2021-04-09€5MStade Rennais FC
2021-06-04€4.5MStade Rennais FC
2021-10-08€3.5MStade Brestois 29
2021-12-16€3.2MStade Brestois 29
2022-05-30€3MStade Brestois 29
2022-11-02€3MStade Brestois 29
2023-06-27€3MStade Brestois 29
2023-10-16€5MStade Brestois 29
2023-12-18€7MStade Brestois 29
2024-03-19€9MStade Brestois 29
2024-06-03€10MStade Brestois 29
2024-12-10€10MStade Brestois 29
2025-03-24€8MStade Brestois 29
2025-06-03€7MStade Brestois 29
2025-12-15€7MStade Brestois 29
2026-06-01€7MStade Brestois 29

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
+0.184

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 54% of the 423 Ligue 1 players.

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

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

Valued above 70% of the 1,583 attackers.

€20k€300k€5M€75M€7MSee them in the Explorer →

Where Castillo 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).