Maas Willemsen
Value picture
Where the market, the likely price and the model estimates sit.
The model rates Maas Willemsen's performance-implied value at EUR 0.4M-1.5M, below the estimated acquisition range of EUR 2.3M-7.0M. Its 24-month market value projection is EUR 2.4M-9.2M. Confidence is medium: no event-level data (xG, progressive actions) is available from the current free source, and injury history is unavailable.
Bargain Index: 47
What drives the score. Not a black box: each component and its level.
| Performance | Below average | 18.2th pct among DEF peers (age-neutral) |
| Age | Favorable | 23.2 years |
| Acquisition cost | Neutral | est. €4.6M vs market €4.5M |
| Expected appreciation | Neutral | +1% over ~2 years (model) |
| Value gap | Very negative | weak predictor on its own |
| Development | Low | |
| League translation | Uncertain | league coefficient 0.43 |
| Tactical fit | Not evaluated | Requires event/role data not available from the current free source. |
| Risk | Moderate | |
| Data confidence | Medium |
Bargain Index = percentile (among all evaluated players) of expected 2-year value relative to estimated cost. See methodology and backtests.
Market value history
Market value ≠ transfer fee ≠ acquisition cost.
Profile vs positional peers
Percentiles among 1268 evaluated DEF players with 900+ minutes.
Performance (last season, league)
- Minutes
- 2559 (84% of available)
- Goals + assists / 90
- 0.04
- Context-adjusted G+A / 90
- 0.05
- xG, xA, progression
- Data unavailable
- Defensive actions
- Data unavailable
- Performance percentile
- 18 (Below average)
Adjusted = shrunk toward positional baseline for small samples, corrected for team dominance over opponents, expressed relative to positional peers in the same league.
Context
- League strength
- 0.43 (rank 15)
- Team strength (Elo)
- 1284
- Opponent strength
- 1308
- Possession, role
- Data unavailable
League strength 1.00 = average club of the big-five leagues. Elo includes continental matches.
Potential
- Development
- Low
- Trajectory
- insufficient
- Breakout probability
- Age > 23
- Resale range (24m)
- €2.4M – €9.2M
Historical comparables (8): median 2-year value change +29% (IQR -5% to +123%).
Risk profile
Overall: Moderate
- ⚠League level coefficient 0.43 (1.00 = big-five average): output may not translate.
- ⚠No continental-competition minutes last season.
- ⚠Projection range wider than for most evaluated players.
- ⓘInjury history unavailable from current data source.
League translation
What happened to players who moved from this league to the big-five leagues (observed, not a forecast).
- Historical movers
- 82 (DEF)
- Relative output kept
- 65%–166%
- Held a regular role (900+ min)
- 78%
- Confidence
- Medium
Output is relative to positional peers in each league. Movers are a selected group (clubs buy players who fit), so treat this as context, not a guarantee.
Season-by-season (domestic league)
Context-adjusted values are model outputs.
| Season | Club | League | Pos | Apps | Min | Min share | G | A | G+A/90 | Adj. G+A/90 | Opp. Elo | Team Elo | League str. |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/26 | SC Heerenveen | Eredivisie | CB | 30 | 2559 | 84% | 1 | 0 | 0.04 | 0.05 | 1308 | 1284 | 0.43 |
Cups & continental competitions
| Season | Competition | Club | Apps | Min | G | A | Avg opp. Elo |
|---|---|---|---|---|---|---|---|
| 2025/26 | Knvb Beker | SC Heerenveen | 4 | 355 | 0 | 0 | — |
Small continental samples are shown for context only and are not over-weighted.
Historical comparables
Most similar profiles 2+ years ago (same position group) and what happened next. Chosen by similarity only — failures included.
| Player (then) | Age | Value then | ~2y later | Outcome |
|---|---|---|---|---|
| Kalidou Koulibaly Jupiler Pro League · 2014 | 23 | €6.5M | €20.0M | rose |
| Eren Elmalı Super Lig · 2023 | 23 | €3.6M | €5.0M | rose |
| Oliver Sonne Superliga · 2024 | 24 | €2.0M | €4.0M | rose |
| Souffian El Karouani Eredivisie · 2024 | 24 | €2.4M | €15.0M | rose |
| Reggie Cannon Liga Portugal · 2021 | 23 | €4.0M | €4.0M | flat |
| Ridgeciano Haps Eredivisie · 2017 | 24 | €5.0M | €4.0M | fell |
| Bernardo Vital Liga Portugal · 2024 | 24 | €2.5M | €3.0M | rose |
| Batista Mendy Super Lig · 2024 | 24 | €9.5M | €7.5M | fell |
Transfer history
Fees as reported by the source; undisclosed fees shown as unknown, never estimated.
| Date | From | To | Fee | MV at time |
|---|---|---|---|---|
| 1 Jul 2025 | De Graafschap | Heerenveen | Free / loan | €500k |
| 1 Jul 2022 | Graafschap U21 | De Graafschap | Unknown | Data unavailable |
| 1 Jul 2020 | Graafschap U17 | Graafschap U21 | Unknown | Data unavailable |
| 1 Jul 2019 | Graafschap Yth. | Graafschap U17 | Unknown | Data unavailable |
| 1 Jul 2014 | FC Twente Youth | Graafschap Yth. | Free / loan | Data unavailable |
MoneyballAI identifies statistical opportunities from available data. A player flagged as a potential bargain is not guaranteed to succeed, to transfer, to rise in value, or to generate resale profit. Market values, fees and contracts come from third-party sources; ranges are model estimates with stated confidence.