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Portrait of Martin Terrier

Martin

Terrier

LWFrance · Bayer 04 Leverkusen

№ 442891Established €3.5M +0.81

Image: FootyLogos

Player dossierBundesliga

MartinTerrier

LWLeft WingerAttack

Club
Bayer 04 Leverkusen
League
Bundesliga
Nationality
France
Age
29
Height
184 cm
Foot
Right
Valued
27 May 2026

Reading the valuation

The market values Terrier at €8M. Model A, which never saw Terrier during training, estimates €3.5M: the market value is 125% above that estimate.

That is a factor of ×2.25. 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 €2.2M, 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.

▲ +0.81A €3.5M▲ +1.29B €2.2M
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
44
Minutes
1,729
Goals
7
Assists
3
Started
20/44
Min / app
39
Cards
2Y 1R

Club matches, two years to the valuation date

The Valuation Journey

What moves Model A

Asking the prediction API to explain Model A for Terrier…

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 €8M

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €8MModel A €3.5M

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

Martin Terrier's percentiles among attackers: Goals per 90 70th, Assists per 90 54th, Minutes, two years 37th, Starts 28th, Minutes, last 365 days 38th, European club minutes 77th70thGoals54thAssists37thMinutes28thStarts38thRecent77thEurope

Dashed ring: the attacker median (50th percentile)

European club minutes

Share of minutes played in UEFA club competitions.

15% this player0% attacker median77th percentile

0%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
€250k
Jan 2017
Peak
€35M
Nov 2022
Model target
€8M
May 2026
Valuations
25
4 club changes
May 2026€8MBayer 04 LeverkusenValuation the model is trained to reproduce

May 2026: €8M, Bayer 04 Leverkusen. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2017-01-16€250kLOSC Lille
2017-06-01€400kLOSC Lille
2018-01-24€12MRC Strasbourg Alsace
2018-06-04€9MRC Strasbourg Alsace
2018-12-17€9MOlympique Lyon
2019-06-03€15MOlympique Lyon
2019-12-19€13MOlympique Lyon
2020-04-08€10.5MOlympique Lyon
2020-08-03€12MStade Rennais FC
2020-10-15€12MStade Rennais FC
2021-06-04€13MStade Rennais FC
2021-12-16€14MStade Rennais FC
2022-03-23€16MStade Rennais FC
2022-05-30€25MStade Rennais FC
2022-09-19€32MStade Rennais FC
2022-11-02€35MStade Rennais FC
2023-06-27€30MStade Rennais FC
2023-12-18€22MStade Rennais FC
2024-03-19€25MStade Rennais FC
2024-06-03€20MStade Rennais FC
2024-12-20€20MBayer 04 Leverkusen
2025-03-27€17MBayer 04 Leverkusen
2025-06-05€17MBayer 04 Leverkusen
2025-12-19€12MBayer 04 Leverkusen
2026-05-27€8MBayer 04 Leverkusen

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
+0.813

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 60% of the 451 Bundesliga players.

€300k€2M€15M€100M€8MSee them in the Explorer →

Attackers, all leagues1,583 players · median €2.5M

Valued above 74% of the 1,583 attackers.

€20k€300k€5M€75M€8MSee them in the Explorer →

Where Terrier 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).