FairValue

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Portrait of Kaishu Sano

Kaishu

Sano

DMJapan · 1.FSV Mainz 05

№ 643574World Class €12.9M +1.13

Image: FootyLogos

Player dossierBundesliga

KaishuSano

DMDefensive MidfieldMidfield

Club
1.FSV Mainz 05
League
Bundesliga
Nationality
Japan
Age
25
Height
176 cm
Foot
Both
Valued
27 May 2026

Reading the valuation

The market values Sano at €40M. Model A, which never saw Sano during training, estimates €12.9M: the market value is 209% above that estimate.

That is a factor of ×3.09. 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 €8.9M, 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.

▲ +1.13A €12.9M▲ +1.51B €8.9M
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
74
Minutes
6,674
Goals
1
Assists
3
Started
74/74
Min / app
90
Cards
4Y 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 Sano…

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 €40M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €40MModel A €12.9M

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 1,687 midfielders

Kaishu Sano's percentiles among midfielders: Goals per 90 20th, Assists per 90 24th, Minutes, two years 97th, Starts 99th, Minutes, last 365 days 97th, European club minutes 62nd20thGoals24thAssists97thMinutes99thStarts97thRecent62ndEurope

Dashed ring: the midfielder median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

100% this player69% midfielder median99th percentile

7%peer deciles · median line · this player ●100%

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
€25k
Jun 2019
Peak
€40M
May 2026
Model target
€40M
May 2026
Valuations
17
2 club changes
May 2026€40M1.FSV Mainz 05Valuation the model is trained to reproduce

May 2026: €40M, 1.FSV Mainz 05. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2019-06-27€25kMachida Zelvia
2019-12-28€250kMachida Zelvia
2021-01-27€500kMachida Zelvia
2021-06-28€500kMachida Zelvia
2022-01-13€650kMachida Zelvia
2022-06-28€700kMachida Zelvia
2023-01-06€750kMachida Zelvia
2023-06-28€800kKashima Antlers
2024-01-09€1MKashima Antlers
2024-06-12€1.5MKashima Antlers
2024-10-09€2.5M1.FSV Mainz 05
2024-12-20€7M1.FSV Mainz 05
2025-03-27€17M1.FSV Mainz 05
2025-06-05€20M1.FSV Mainz 05
2025-10-14€25M1.FSV Mainz 05
2025-12-19€25M1.FSV Mainz 05
2026-05-27€40M1.FSV Mainz 05

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
+1.129

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 93% of the 451 Bundesliga players.

€300k€2M€15M€100M€40MSee them in the Explorer →

Midfielders, all leagues1,687 players · median €2M

Valued above 96% of the 1,687 midfielders.

€20k€200k€2M€20M€40MSee them in the Explorer →

Where Sano 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).