FairValue

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Panagiotis

Retsos

CBGreece · Olympiacos Piraeus

№ 324351Established €5.7M +0.21

Player dossierSuper League

PanagiotisRetsos

CBCentre-BackDefender

Club
Olympiacos Piraeus
League
Super League
Nationality
Greece
Age
27
Height
186 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Retsos at €7M. Model A, which never saw Retsos during training, estimates €5.7M: the market value is 23% above that estimate.

That is a factor of ×1.23. 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 €4.7M, 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.

▲ +0.21A €5.7M▲ +0.40B €4.7M
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
59
Minutes
4,662
Goals
4
Assists
1
Started
53/59
Min / app
79
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 Retsos…

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 €5.7M

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 2,065 defenders

Panagiotis Retsos's percentiles among defenders: Goals per 90 79th, Assists per 90 37th, Minutes, two years 78th, Starts 68th, Minutes, last 365 days 80th, European club minutes 96th79thGoals37thAssists78thMinutes68thStarts80thRecent96thEurope

Dashed ring: the defender median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

32% this player0% defender median96th 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
€200k
Oct 2016
Peak
€18M
Dec 2017
Model target
€7M
Jun 2026
Valuations
26
6 club changes
Jun 2026€7MOlympiacos PiraeusValuation the model is trained to reproduce

Jun 2026: €7M, Olympiacos Piraeus. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-10-01€200kOlympiacos Piraeus
2016-12-21€1MOlympiacos Piraeus
2017-05-11€2.5MOlympiacos Piraeus
2017-08-21€5MOlympiacos Piraeus
2017-10-18€12MBayer 04 Leverkusen
2017-12-28€18MBayer 04 Leverkusen
2018-06-05€18MBayer 04 Leverkusen
2018-12-18€15MBayer 04 Leverkusen
2019-06-05€13MBayer 04 Leverkusen
2019-10-02€9MBayer 04 Leverkusen
2019-12-17€9MBayer 04 Leverkusen
2020-04-08€8MSheffield United
2020-10-15€6MAS Saint-Étienne
2021-04-09€5MAS Saint-Étienne
2021-06-04€4.5MAS Saint-Étienne
2021-12-22€3.5MBayer 04 Leverkusen
2022-06-07€2.8MHellas Verona
2022-11-07€2.5MOlympiacos Piraeus
2023-05-22€2MOlympiacos Piraeus
2023-12-20€2.5MOlympiacos Piraeus
2024-05-30€2.5MOlympiacos Piraeus
2024-09-26€3MOlympiacos Piraeus
2024-12-18€4.5MOlympiacos Piraeus
2025-05-23€5MOlympiacos Piraeus
2025-12-12€6MOlympiacos Piraeus
2026-06-04€7MOlympiacos Piraeus

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
+0.210

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 →

Super League356 players · median €600k

Joint 9th highest observed value among 356 Super League players.

€20k€150k€1M€7.5M€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 Retsos 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).