Jens
Toornstra
AMNetherlands · Sparta Rotterdam
Player dossierEredivisie
JensToornstra
AMAttacking MidfieldMidfield
- Club
- Sparta Rotterdam
- League
- Eredivisie
- Nationality
- Netherlands
- Age
- 37
- Height
- 178 cm
- Foot
- Right
- Valued
- 28 May 2026
Reading the valuation
The market values Toornstra at €200k. Model A, which never saw Toornstra during training, estimates €124k: the market value is 61% above that estimate.
That is a factor of ×1.61. 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 €173k, closer to the market here, although it is usually further off (typical miss ×2.07).
A gap describes the model's arithmetic for this player's inputs, not what the player is worth.
- Apps
- 53
- Minutes
- 2,515
- Goals
- 1
- Assists
- 5
- Started
- 30/53
- Min / app
- 47
- Cards
- 5Y 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 Toornstra…
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 €200k
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 1,687 midfielders
Dashed ring: the midfielder median (50th percentile)
Assists per 90
Club assists per 90 minutes in the same window.
0.18 this player0.09 midfielder median78th 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
- Dec 2009
- Peak
- €7.5M
- Jun 2017
- Model target
- €200k
- May 2026
- Valuations
- 39
- 5 club changes
May 2026: €200k, Sparta Rotterdam. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2009-12-07 | €50k | ADO Den Haag U21 |
| 2010-08-25 | €500k | ADO Den Haag |
| 2011-01-17 | €750k | ADO Den Haag |
| 2011-03-08 | €1M | ADO Den Haag |
| 2011-06-17 | €1.8M | ADO Den Haag |
| 2012-01-20 | €2M | ADO Den Haag |
| 2013-01-14 | €2.5M | ADO Den Haag |
| 2013-06-04 | €2.8M | FC Utrecht |
| 2013-09-26 | €3.5M | FC Utrecht |
| 2014-02-11 | €3.5M | FC Utrecht |
| 2014-08-11 | €4M | FC Utrecht |
| 2015-02-16 | €6M | Feyenoord Rotterdam |
| 2015-07-01 | €6M | Feyenoord Rotterdam |
| 2015-11-11 | €5M | Feyenoord Rotterdam |
| 2016-02-05 | €4M | Feyenoord Rotterdam |
| 2016-07-15 | €4M | Feyenoord Rotterdam |
| 2017-01-18 | €6M | Feyenoord Rotterdam |
| 2017-06-07 | €7.5M | Feyenoord Rotterdam |
| 2018-01-17 | €6M | Feyenoord Rotterdam |
| 2018-06-12 | €5M | Feyenoord Rotterdam |
| 2018-12-28 | €4M | Feyenoord Rotterdam |
| 2019-06-12 | €4M | Feyenoord Rotterdam |
| 2019-12-18 | €4M | Feyenoord Rotterdam |
| 2020-04-08 | €3.2M | Feyenoord Rotterdam |
| 2020-10-14 | €2.5M | Feyenoord Rotterdam |
| 2021-01-06 | €2.2M | Feyenoord Rotterdam |
| 2021-03-09 | €2M | Feyenoord Rotterdam |
| 2021-05-19 | €2M | Feyenoord Rotterdam |
| 2022-01-05 | €1.5M | Feyenoord Rotterdam |
| 2022-06-08 | €1.2M | Feyenoord Rotterdam |
| 2022-09-14 | €1M | FC Utrecht |
| 2022-11-11 | €1M | FC Utrecht |
| 2023-06-23 | €750k | FC Utrecht |
| 2023-12-15 | €550k | FC Utrecht |
| 2024-05-31 | €450k | FC Utrecht |
| 2024-12-17 | €350k | FC Utrecht |
| 2025-05-28 | €350k | FC Utrecht |
| 2025-12-02 | €300k | Sparta Rotterdam |
| 2026-05-28 | €200k | Sparta Rotterdam |
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
- +0.474
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 →Eredivisie425 players · median €1M
Valued above 3% of the 425 Eredivisie players.
See them in the Explorer →Midfielders, all leagues1,687 players · median €2M
Valued above 3% of the 1,687 midfielders.
See them in the Explorer →Where Toornstra appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- WolfswinkelCFFC Twente Enschede · Eredivisie€200k
- NuytinckCBNEC Nijmegen · Eredivisie€200k
- WierikCBHeracles Almelo · Eredivisie€200k
- AmevorCBFC Volendam · Eredivisie€200k
- CazorlaCMReal Oviedo · midfielders€200k
- KvekveskiriDMFC Orenburg · midfielders€200k
- VillafañezAMAE Kifisia · midfielders€200k
- ArmstrongCMAberdeen FC · midfielders€200k
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).