FairValue

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Sebastian

Walukiewicz

RBPoland · US Sassuolo

№ 345458Established €6.8M −0.31

Player dossierSerie A

SebastianWalukiewicz

RBRight-BackDefender

Club
US Sassuolo
League
Serie A
Nationality
Poland
Age
26
Height
188 cm
Foot
Right
Valued
29 May 2026

Reading the valuation

The market values Walukiewicz at €5M. Model A, which never saw Walukiewicz during training, estimates €6.8M: the market value is 27% below that estimate.

That is a factor of ×1.36. 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 €6.2M, 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.

▼ −0.31A €6.8M▼ −0.21B €6.2M
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
68
Minutes
4,852
Goals
0
Assists
1
Started
57/68
Min / app
71
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 Walukiewicz…

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 €5M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €5MModel A €6.8M

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 2,065 defenders

Sebastian Walukiewicz's percentiles among defenders: Goals per 90 18th, Assists per 90 37th, Minutes, two years 81st, Starts 53rd, Minutes, last 365 days 88th, European club minutes 30th18thGoals37thAssists81stMinutes53rdStarts88thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Minutes, last 365 days

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

2,965 this player1,687 defender median88th percentile

0peer deciles · median line · this player ●4,941

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
€75k
Jul 2017
Peak
€10M
Dec 2020
Model target
€5M
May 2026
Valuations
23
4 club changes
May 2026€5MUS SassuoloValuation the model is trained to reproduce

May 2026: €5M, US Sassuolo. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-07-05€75kPogon Szczecin
2018-01-16€75kPogon Szczecin
2018-07-03€200kPogon Szczecin
2019-01-25€4MPogon Szczecin
2019-06-29€4MPogon Szczecin
2019-12-12€4MCagliari Calcio
2020-04-08€3.6MCagliari Calcio
2020-08-25€4MCagliari Calcio
2020-10-29€7MCagliari Calcio
2020-12-29€10MCagliari Calcio
2021-06-03€7.5MCagliari Calcio
2021-12-28€7MCagliari Calcio
2022-06-07€5MCagliari Calcio
2022-11-11€3.5MFC Empoli
2023-03-21€3MFC Empoli
2023-06-15€3MFC Empoli
2023-12-20€2.5MFC Empoli
2024-06-05€2.5MFC Empoli
2024-10-18€5MTorino FC
2024-12-18€5MTorino FC
2025-06-17€4.5MTorino FC
2025-12-23€4.5MUS Sassuolo
2026-05-29€5MUS Sassuolo

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
−0.309

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 45% of the 507 Serie A players.

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

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

Valued above 70% of the 2,065 defenders.

€20k€200k€2M€20M€5MSee them in the Explorer →

Where Walukiewicz 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).