Borja
Sainz
LWSpain · FC Porto
Player dossierLiga Portugal
BorjaSainz
LWLeft WingerAttack
- Club
- FC Porto
- League
- Liga Portugal
- Nationality
- Spain
- Age
- 25
- Height
- 174 cm
- Foot
- Right
- Valued
- 28 May 2026
Liga PortugalReading the valuation
The market values Sainz at €20M. Model A, which never saw Sainz during training, estimates €13.7M: the market value is 46% above that estimate.
That is a factor of ×1.46. 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 €6.4M, 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
- 43
- Minutes
- 2,340
- Goals
- 6
- Assists
- 6
- Started
- 28/43
- Min / app
- 54
- Cards
- 7Y 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 Sainz…
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 €20M
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 1,583 attackers
Dashed ring: the attacker median (50th percentile)
European club minutes
Share of minutes played in UEFA club competitions.
29% this player0% attacker median93rd 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
- €300k
- Dec 2019
- Peak
- €23M
- Dec 2025
- Model target
- €20M
- May 2026
- Valuations
- 18
- 4 club changes
May 2026: €20M, FC Porto. Dotted lines mark the €2M, €10M and €30M tier boundaries.
Show as a table
| Date | Market value | Club |
|---|---|---|
| 2019-12-20 | €300k | Deportivo Alavés |
| 2020-07-23 | €2.5M | Deportivo Alavés |
| 2020-10-08 | €2.5M | Deportivo Alavés |
| 2021-01-05 | €2.5M | Deportivo Alavés |
| 2021-06-10 | €2M | Deportivo Alavés |
| 2021-12-27 | €2.2M | Real Zaragoza |
| 2022-06-29 | €2.2M | Real Zaragoza |
| 2022-10-27 | €2.2M | Giresunspor |
| 2023-03-14 | €2.2M | Giresunspor |
| 2023-06-08 | €2.2M | Giresunspor |
| 2023-12-21 | €2.2M | Norwich City |
| 2024-05-24 | €2.2M | Norwich City |
| 2024-12-30 | €12M | Norwich City |
| 2025-05-27 | €14M | Norwich City |
| 2025-09-30 | €20M | FC Porto |
| 2025-12-18 | €23M | FC Porto |
| 2026-03-19 | €22M | FC Porto |
| 2026-05-28 | €20M | FC Porto |
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
- +0.380
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 →Liga Portugal423 players · median €1M
Valued above 93% of the 423 Liga Portugal players.
See them in the Explorer →Attackers, all leagues1,583 players · median €2.5M
Valued above 87% of the 1,583 attackers.
See them in the Explorer →Where Sainz appears
Watchlists and the comparison tray are kept in this browser only.
Near this valuation closest observed values: same league, then same position
- PrestianniRWSL Benfica · Liga Portugal€20M
- BarreiroCMSL Benfica · Liga Portugal€18M
- HornicekGKSC Braga · Liga Portugal€18M
- CostaRBFC Porto · Liga Portugal€18M
- SanéRWGalatasaray · attackers€20M
- GrealishLWEverton FC · attackers€20M
- IwobiLWFulham FC · attackers€20M
- AktürkoğluLWFenerbahce · attackers€20M
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).