FairValue

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Portrait of Serhou Guirassy

Serhou

Guirassy

CFGuinea · Borussia Dortmund

№ 270541World Class €45.6M −0.35

Image: FootyLogos

Player dossierBundesliga

SerhouGuirassy

CFCentre-ForwardAttack

Club
Borussia Dortmund
League
Bundesliga
Nationality
Guinea
Age
30
Height
187 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Guirassy at €32M. Model A, which never saw Guirassy during training, estimates €45.6M: the market value is 30% below that estimate.

That is a factor of ×1.42. 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 €46.4M, 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.

▼ −0.35A €45.6M▼ −0.37B €46.4M
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
96
Minutes
7,462
Goals
60
Assists
15
Started
84/96
Min / app
78
Cards
10Y 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 Guirassy…

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 €45.6M

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 1,583 attackers

Serhou Guirassy's percentiles among attackers: Goals per 90 98th, Assists per 90 63rd, Minutes, two years 99th, Starts 91st, Minutes, last 365 days 99th, European club minutes 94th98thGoals63rdAssists99thMinutes91stStarts99thRecent94thEurope

Dashed ring: the attacker median (50th percentile)

Minutes, two years

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

7,462 this player2,242 attacker median99th percentile

450peer deciles · median line · this player ●8,788

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
Nov 2014
Peak
€45M
Jun 2025
Model target
€32M
May 2026
Valuations
32
8 club changes
May 2026€32MBorussia DortmundValuation the model is trained to reproduce

May 2026: €32M, Borussia Dortmund. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2014-11-20€200kStade Lavallois
2015-01-14€300kStade Lavallois
2015-06-06€400kStade Lavallois
2015-09-06€500kLOSC Lille
2016-02-04€800kAJ Auxerre
2016-07-13€2MLOSC Lille
2017-02-07€2M1.FC Köln
2017-06-19€1.5M1.FC Köln
2017-12-28€3.5M1.FC Köln
2018-06-05€2.5M1.FC Köln
2019-01-08€2M1.FC Köln
2019-06-03€3.5MAmiens SC
2019-09-27€5MAmiens SC
2019-12-19€5MAmiens SC
2020-03-13€10MAmiens SC
2020-04-08€8MAmiens SC
2020-10-15€15MStade Rennais FC
2021-01-07€13MStade Rennais FC
2021-04-09€12MStade Rennais FC
2021-06-04€12MStade Rennais FC
2021-12-16€9MStade Rennais FC
2022-03-23€10MStade Rennais FC
2022-05-30€10MStade Rennais FC
2022-11-09€10MVfB Stuttgart
2023-06-22€14MVfB Stuttgart
2023-10-18€40MVfB Stuttgart
2023-12-14€40MVfB Stuttgart
2024-05-29€40MVfB Stuttgart
2024-12-20€40MBorussia Dortmund
2025-06-05€45MBorussia Dortmund
2025-12-19€40MBorussia Dortmund
2026-05-27€32MBorussia Dortmund

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
−0.353

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 →

Bundesliga451 players · median €5M

Valued above 91% of the 451 Bundesliga players.

€300k€2M€15M€100M€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 Guirassy 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).