FairValue

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Marios

Vrousai

RBGreece · Rio Ave FC

№ 395632Established €1.6M +0.65

Player dossierLiga Portugal

MariosVrousai

RBRight-BackDefender

Club
Rio Ave FC
League
Liga Portugal
Nationality
Greece
Age
27
Height
183 cm
Foot
Right
Valued
28 May 2026

Reading the valuation

The market values Vrousai at €3M. Model A, which never saw Vrousai during training, estimates €1.6M: the market value is 91% above that estimate.

That is a factor of ×1.91. 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 €3.9M, 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.

▲ +0.65A €1.6M▼ −0.25B €3.9M
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
62
Minutes
5,079
Goals
2
Assists
5
Started
58/62
Min / app
82
Cards
8Y 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 Vrousai…

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 €3M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €3MModel A €1.6M

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

Marios Vrousai's percentiles among defenders: Goals per 90 53rd, Assists per 90 74th, Minutes, two years 84th, Starts 80th, Minutes, last 365 days 77th, European club minutes 30th53rdGoals74thAssists84thMinutes80thStarts77thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, two years

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

5,079 this player2,860 defender median84th percentile

451peer deciles · median line · this player ●9,111

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
Dec 2016
Peak
€3M
May 2026
Model target
€3M
May 2026
Valuations
19
3 club changes
May 2026€3MRio Ave FCValuation the model is trained to reproduce

May 2026: €3M, Rio Ave FC. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2016-12-21€150kOlympiacos Piraeus
2018-05-21€200kOlympiacos Piraeus
2018-12-07€200kOlympiacos Piraeus
2019-03-13€750kWillem II Tilburg
2019-06-12€1MWillem II Tilburg
2019-12-18€1MWillem II Tilburg
2020-04-08€900kWillem II Tilburg
2020-10-12€900kOlympiacos Piraeus
2021-02-12€1.5MOlympiacos Piraeus
2021-11-01€1.5MOlympiacos Piraeus
2022-06-09€1.5MOlympiacos Piraeus
2022-11-07€1MOlympiacos Piraeus
2023-05-22€900kOlympiacos Piraeus
2023-12-20€800kOlympiacos Piraeus
2024-06-06€1MRio Ave FC
2024-12-19€1.5MRio Ave FC
2025-05-30€2MRio Ave FC
2025-12-18€2.5MRio Ave FC
2026-05-28€3MRio Ave FC

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
+0.648

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 →

Liga Portugal423 players · median €1M

Valued above 67% of the 423 Liga Portugal players.

€20k€200k€2M€20M€3MSee them in the Explorer →

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

Valued above 59% of the 2,065 defenders.

€20k€200k€2M€20M€3MSee them in the Explorer →

Where Vrousai 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).