Jae-sung Lee

34 yrs · Attacking midfielder · Korea, South
1.FSV Mainz 05 · Bundesliga · Foot: left · Height: 180 cm
Risk: ModerateConfidence: MediumSample: HighDevelopment: LowContract: Data unavailable
Market value
€2.0M
Updated 6 days ago
Estimated acquisition
€636k – €2.4M
Estimated · 20–80% range
Model value
€1.4M – €3.3M
Performance-implied · estimated
Projected (24m)
€484k – €1.5M
Resale range · estimated
Potential value gap
-€1.0M – €2.6M
Model value − acquisition

Value picture

Where the market, the likely price and the model estimates sit.

Estimated acquisition€636k – €2.4M
Model value (performance-implied)€1.4M – €3.3M
Projected value (24 months)€484k – €1.5M
Dashed line: current market value (€2.0M). Bars are 20–80% model ranges; tick = median.

The model rates Jae-sung Lee's performance-implied value at EUR 1.4M-3.3M, above the estimated acquisition range of EUR 0.6M-2.4M. Its 24-month market value projection is EUR 0.5M-1.5M. Context-adjusted goal contributions are 0.74x the positional average in the league (2201 minutes, league coefficient 0.94). Confidence is medium: no event-level data (xG, progressive actions) is available from the current free source, and injury history is unavailable.

Acquisition note: Contract end date unavailable: range widened by 15% each side.

Bargain Index: not assigned

What drives the score. Not a black box: each component and its level.

Age above 33 (outside validated pool)

PerformanceHigh85.4th pct among MID peers (age-neutral)
AgeUnfavorable33.9 years
Acquisition costFavorableest. €1.2M vs market €2.0M
Expected appreciationVery low-54% over ~2 years (model)
Value gapVery largeweak predictor on its own
DevelopmentLow
League translationBig-five leagueleague coefficient 0.94
Tactical fitNot evaluatedRequires event/role data not available from the current free source.
RiskModerate
Data confidenceMedium

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.

Highest recorded: €4.0M

Profile vs positional peers

Percentiles among 1163 evaluated MID players with 900+ minutes.

Performance (last season, league)

Minutes
2201 (72% of available)
Goals + assists / 90
0.24
Context-adjusted G+A / 90
0.30
xG, xA, progression
Data unavailable
Defensive actions
Data unavailable
Performance percentile
85 (High)

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
0.94 (rank 3)
Team strength (Elo)
1485
Opponent strength
1491
Possession, role
Data unavailable

League strength 1.00 = average club of the big-five leagues. Elo includes continental matches.

Potential

Development
Low
Trajectory
declining
Breakout probability
Age > 23
Resale range (24m)
€484k – €1.5M

Trajectory drivers: minutes share down 15 pts; relative output down 34% vs positional peers.

Historical comparables (8): median 2-year value change -68% (IQR -76% to -60%).

Risk profile

Overall: Moderate

  • ▲Age 34: resale value typically declines.
  • ⚠Declining trajectory versus previous season.
  • ⓘContract end date unavailable (or stale in source).
  • ⓘ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).

Already playing in a big-five league.

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.

SeasonClubLeaguePosAppsMinMin shareGAG+A/90Adj. G+A/90Opp. EloTeam EloLeague str.
2025/261.FSV Mainz 05BundesligaAM28220172%420.250.30149114850.94
2024/251.FSV Mainz 05BundesligaAM33266687%780.510.44151015150.94
2023/241.FSV Mainz 05BundesligaAM29212870%640.420.43152514891.01
2022/231.FSV Mainz 05BundesligaAM34190462%740.520.40152614961.04
2021/221.FSV Mainz 05BundesligaAM27144947%430.430.39150715071.05

Cups & continental competitions

SeasonCompetitionClubAppsMinGAAvg opp. Elo
2025/26Uefa Conference League Qualifying1.FSV Mainz 052172101335
2025/26World CupSouth Korea211900—
2025/26Dfb Pokal1.FSV Mainz 0527500—
2024/25Dfb Pokal1.FSV Mainz 05111101—
2023/24Dfb Pokal1.FSV Mainz 05213900—
2022/23Dfb Pokal1.FSV Mainz 05211000—
2021/22Dfb Pokal1.FSV Mainz 05317800—

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)AgeValue then~2y laterOutcome
Nicolas Höfler
Bundesliga · 2024
34€2.0M€500kfell
Florent Balmont
Ligue 1 · 2013
33€2.0M€500kfell
Glenn Whelan
Premier League · 2017
33€2.5M€1.0Mfell
Blagoy Georgiev
Premier Liga · 2014
33€1.5M€300kfell
Ugur Inceman
Super Lig · 2013
32€1.3M€200kfell
Gareth Barry
Premier League · 2016
35€2.5M€1.0Mfell
Roberto Trashorras
Laliga · 2013
32€2.0M€1.5Mfell
Daniel Baier
Bundesliga · 2018
34€1.0M€400kfell

Transfer history

Fees as reported by the source; undisclosed fees shown as unknown, never estimated.

DateFromToFeeMV at time
8 Jul 2021Holstein KielMainzFree / loan€3.0M
26 Jul 2018Jeonbuk HyundaiHolstein Kiel€900k€2.0M
1 Jan 2014Korea UniversityJeonbuk HyundaiFree / loanData unavailable
1 Jan 2011Haksung HSKorea UniversityUnknownData unavailable
1 Jan 2008U. Haksung MSHaksung HSUnknownData unavailable
1 Jan 2005U. Okdong ESU. Haksung MSUnknownData 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.