Domestic-league season · Stuttgart II.
Missed 10 of Stuttgart II's ~38 games this season through 10 injury absences (ankle, injured doubtful, muscle). He still appeared 21 times — a solid return given how little of the season he was available. His rating is judged mainly on the games he was fit to play.
| Competition | Apps | G | A | Min | Match |
|---|---|---|---|---|---|
 3. Liga | 21 | 2 | 2 | 721 | 6.96 |
Diehl's current-season form is up 233% on last season (Season 3→10), while his Rating climbed 38→41. That makes this his strongest season for form to date.
| Season | Club | Apps | G | A | Match | RTG | Season |
|---|---|---|---|---|---|---|---|
| 2025/26 | Stuttgart II · 14th | 21 | 2 | 2 | 6.96 | 41 | 10 |
| 2024/25 | Stuttgart II · 15th | 4 | 1 | 0 | 6.88 | 38 | 3 |
| 2023/24 | 1. FC Köln · 17th | 7 | 0 | 0 | 6.63 | 63 | 0 |
| 2022/23 | 1. FC Köln · 11th | 4 | 0 | 0 | 6.25 | 64 | 0 |
Domestic-league totals per season. RTG = Field Insider Rating (potential / ceiling); Season = age-blind form that year.
J. Diehl is a 21-year-old attacking midfielder at Stuttgart II, rated 40.6 overall by Field Insider's model, ranking 62nd of 315 in the 3. Liga and 2056th of 3060 U-23 players tracked. A young player, he has been a fringe squad member this season (21.1% of available minutes). He brings 0.5 goal contributions per 90 (0.25 goals, 0.25 assists). Below: strengths, watch-points, market-value outlook and the latest transfer news on Diehl.
Judged on this season alone, Diehl graded 10 — a workmanlike campaign that ranks 20th of 23 of the 23 attacking midfielders in the 3. Liga, on 2 goals and 2 assists in 21 appearances (0.499 involvements per 90).
Year-on-year, that's a clear step up on last season (Season 3 → 10). Across the 4 seasons we hold, it's his best return yet.
On long-term talent our Rating reads 41, top 31% of the 23 attacking midfielders in the 3. Liga. At 21 Diehl is still climbing toward his ceiling, and a market index of 19 reflects that trajectory.
Read the appearance count in context: Diehl missed 10 games through injury (ankle, injured doubtful, muscle) out of roughly 38 this season. The 21 he did play is a solid return on the time he was fit, and his ratings are weighted toward those games rather than the ones he sat out injured.
2 goals in 21 appearances (0.1 per game) — light end product the role wants to see climb. Add 2 assists for 4 goal contributions in all.
With a Rating of 40.6, Diehl carries the 7th-highest potential of the attacking midfielders in the 3. Liga of 23 — though on just 21 appearances this season, so the standing rests on a small sample. In the final third he profiles as a productive contributor (0.5 goal contributions per 90). At 21 the trajectory points up — potential sits near its ceiling (97/100) and market value should climb as minutes and output follow.
Generated from Field Insider's rating model · AI-written analysis to follow.
The gold line is market value — an index (not €) blending rating, age and league. It climbs through the early 20s, peaks around ages 23–27 (~21), then tapers with age. At 21, Diehl sits on 19, still climbing toward its peak. The blue line is Diehl's projected Rating — 40.6 today — recomputed at each age, so it follows the same rise-and-fall as a career matures and declines. Solid = up to today; dashed = projected.
No transfer news found for this player.
