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Konstantinos

Triantafyllopoulos

CBGreece · Asteras Aktor

№ 185691Emerging €249k −0.35

Player dossierSuper League

KonstantinosTriantafyllopoulos

CBCentre-BackDefender

Club
Asteras Aktor
League
Super League
Nationality
Greece
Age
33
Height
185 cm
Foot
Right
Valued
4 Jun 2026

Reading the valuation

The market values Triantafyllopoulos at €175k. Model A, which never saw Triantafyllopoulos during training, estimates €249k: 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 €362k, 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 €249k▼ −0.73B €362k
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
46
Minutes
3,692
Goals
1
Assists
1
Started
41/46
Min / app
80
Cards
8Y 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 Triantafyllopoulos…

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 €175k

Checking API
EmergingEstablishedEliteWorld Class€2M€10M€30M€100k€1M€100MMarket €175kModel A €249k

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

Konstantinos Triantafyllopoulos's percentiles among defenders: Goals per 90 44th, Assists per 90 40th, Minutes, two years 65th, Starts 67th, Minutes, last 365 days 45th, European club minutes 30th44thGoals40thAssists65thMinutes67thStarts45thRecent30thEurope

Dashed ring: the defender median (50th percentile)

Starts

Share of appearances started rather than entered from the bench.

89% this player83% defender median67th percentile

18%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
€150k
Jul 2012
Peak
€1.8M
Apr 2022
Model target
€175k
Jun 2026
Valuations
37
4 club changes
Jun 2026€175kAsteras AktorValuation the model is trained to reproduce

Jun 2026: €175k, Asteras Aktor. Dotted lines mark the €2M, €10M and €30M tier boundaries.

Show as a table
DateMarket valueClub
2012-07-12€150kPanathinaikos
2012-08-26€250kPanathinaikos
2012-09-21€250kPanathinaikos
2013-02-10€450kPanathinaikos
2013-12-02€750kPanathinaikos
2014-03-28€1MPanathinaikos
2014-11-11€1MPanathinaikos
2015-05-10€1.3MPanathinaikos
2015-09-27€1MPanathinaikos
2016-02-21€800kAsteras Tripolis
2016-06-21€600kAsteras Tripolis
2016-12-21€450kAsteras Tripolis
2017-05-11€450kAsteras Tripolis
2017-12-18€500kAsteras Tripolis
2018-05-22€700kAsteras Tripolis
2018-12-07€600kAsteras Tripolis
2019-05-21€500kAsteras Tripolis
2020-01-15€750kPogon Szczecin
2020-04-08€600kPogon Szczecin
2020-08-18€750kPogon Szczecin
2021-01-19€750kPogon Szczecin
2021-05-21€850kPogon Szczecin
2021-10-15€1MPogon Szczecin
2021-12-31€1.5MPogon Szczecin
2022-04-07€1.8MPogon Szczecin
2022-06-14€1.8MPogon Szczecin
2022-09-29€1.5MPogon Szczecin
2022-11-16€800kPogon Szczecin
2023-06-09€600kPogon Szczecin
2023-10-06€450kGórnik Zabrze
2023-12-29€300kGórnik Zabrze
2024-03-28€200kGórnik Zabrze
2024-06-07€200kGórnik Zabrze
2024-12-18€200kAsteras Aktor
2025-05-23€200kAsteras Aktor
2025-12-12€200kAsteras Aktor
2026-06-04€175kAsteras Aktor

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
−0.351

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 →

Super League356 players · median €600k

Valued above 8% of the 356 Super League players.

€20k€150k€1M€7.5M€175kSee them in the Explorer →

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

Valued above 5% of the 2,065 defenders.

€20k€200k€2M€20M€175kSee them in the Explorer →

Where Triantafyllopoulos 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).