Patrick
Mainka
Player dossierBundesliga
PatrickMainka
CBCentre-BackDefender
- Club
- 1.FC Heidenheim 1846
- League
- Bundesliga
- Nationality
- Germany
- Age
- 31
- Height
- 194 cm
- Foot
- Right
- Valued
- 27 May 2026
Reading the valuation
The market values Mainka at €2.5M. Model A, which never saw Mainka during training, estimates €2.7M: the market value is 7% below that estimate.
That is a factor of ×1.08. 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 €2.8M, 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.
- Apps
- 73
- Minutes
- 6,554
- Goals
- 3
- Assists
- 3
- Started
- 73/73
- Min / app
- 90
- Cards
- 6Y 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 Mainka…
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 €2.5M
Checking APIAsking 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
Dashed ring: the defender median (50th percentile)
Starts
Share of appearances started rather than entered from the bench.
100% this player83% defender median97th percentile
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
- €50k
- Feb 2013
- Peak
- €3M
- Oct 2024
- Model target
- €2.5M
- May 2026
- Valuations
- 34
- 4 club changes
May 2026: €2.5M, 1.FC Heidenheim 1846. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2013-02-06 | €50k | Arminia Bielefeld U19 |
| 2013-06-28 | €50k | Arminia Bielefeld U19 |
| 2014-01-20 | €100k | Arminia Bielefeld II |
| 2014-06-30 | €100k | Arminia Bielefeld II |
| 2014-08-18 | €100k | SV Werder Bremen II |
| 2015-02-08 | €125k | SV Werder Bremen II |
| 2015-07-01 | €150k | SV Werder Bremen II |
| 2016-01-15 | €150k | Borussia Dortmund II |
| 2016-07-15 | €150k | Borussia Dortmund II |
| 2016-11-20 | €175k | Borussia Dortmund II |
| 2017-07-01 | €200k | Borussia Dortmund II |
| 2018-02-03 | €200k | Borussia Dortmund II |
| 2018-08-21 | €300k | 1.FC Heidenheim 1846 |
| 2018-10-16 | €600k | 1.FC Heidenheim 1846 |
| 2019-01-08 | €850k | 1.FC Heidenheim 1846 |
| 2019-06-12 | €1.3M | 1.FC Heidenheim 1846 |
| 2019-12-13 | €1.3M | 1.FC Heidenheim 1846 |
| 2020-04-02 | €1.5M | 1.FC Heidenheim 1846 |
| 2020-04-08 | €1.2M | 1.FC Heidenheim 1846 |
| 2020-07-15 | €1.5M | 1.FC Heidenheim 1846 |
| 2021-02-08 | €1.7M | 1.FC Heidenheim 1846 |
| 2021-03-29 | €2M | 1.FC Heidenheim 1846 |
| 2021-06-16 | €2M | 1.FC Heidenheim 1846 |
| 2021-12-15 | €1.8M | 1.FC Heidenheim 1846 |
| 2022-06-16 | €1.8M | 1.FC Heidenheim 1846 |
| 2022-11-30 | €1.8M | 1.FC Heidenheim 1846 |
| 2023-06-28 | €2M | 1.FC Heidenheim 1846 |
| 2023-12-14 | €2.5M | 1.FC Heidenheim 1846 |
| 2024-05-29 | €2.5M | 1.FC Heidenheim 1846 |
| 2024-10-09 | €3M | 1.FC Heidenheim 1846 |
| 2024-12-20 | €3M | 1.FC Heidenheim 1846 |
| 2025-06-05 | €3M | 1.FC Heidenheim 1846 |
| 2025-12-19 | €2.5M | 1.FC Heidenheim 1846 |
| 2026-05-27 | €2.5M | 1.FC Heidenheim 1846 |
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
- −0.078
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 25% of the 451 Bundesliga players.
See them in the Explorer →Defenders, all leagues2,065 players · median €2M
Valued above 54% of the 2,065 defenders.
See them in the Explorer →Where Mainka appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- KramaricSSTSG 1899 Hoffenheim · Bundesliga€2.5M
- BaumannGKTSG 1899 Hoffenheim · Bundesliga€2.5M
- EriksenAMVfL Wolfsburg · Bundesliga€2.5M
- CoufalRBTSG 1899 Hoffenheim · Bundesliga€2.5M
- GraditCBRC Lens · defenders€2.5M
- StarkCBSV Werder Bremen · defenders€2.5M
- MataCBOlympique Lyon · defenders€2.5M
- WolfRBFC Augsburg · defenders€2.5M
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).



