Domestic-league season · Lecce.
Parent club Fortuna Düsseldorf — 2. Bundesliga: 2 apps, 0g 0a, 180 min
Parent club Fortuna Düsseldorf — DFB Pokal: 1 apps, 0g 0a, 90 min
The headline Season rating covers his time at Lecce; availability counts only fixtures while in this squad.
| Competition | Apps | G | A | Min | Match |
|---|---|---|---|---|---|
 Serie A | 21 | 1 | 0 | 1707 | 6.85 |
 UEFA U21 Championship - Qualificationat Germany U21 | 3 | 0 | 0 | 239 | — |
 2. Bundesligaat Fortuna Düsseldorf | 2 | 0 | 0 | 180 | 6.6 |
 UEFA U21 Championshipat Germany U21 | 5 | 0 | 0 | 100 | 6.45 |
 DFB Pokalat Fortuna Düsseldorf | 1 | 0 | 0 | 90 | 6.6 |
 Coppa Italia | 1 | 0 | 0 | 18 | 4.3 |
Following his move to Lecce, Siebert's current-season form is level with last season (Season 26→24), while his Rating climbed 62→70. His peak season for form remains 2023/24 (Season 31).
| Season | Club | Apps | G | A | Match | RTG | Season |
|---|---|---|---|---|---|---|---|
| 2025/26 | Lecce · 17th | 21 | 1 | 0 | 6.85 | 70 | 24 |
| 2024/25 | Fortuna Düsseldorf · 6th | 21 | 0 | 2 | 6.71 | 62 | 26 |
| 2023/24 | Fortuna Düsseldorf · 3rd | 24 | 1 | 1 | 6.94 | 64 | 31 |
| 2022/23 | FC Viktoria Köln · 9th | 30 | 2 | 0 | — | 44 | 7 |
| 2021/22 | FC Viktoria Köln · 13th | 13 | 0 | 0 | — | 39 | 7 |
| 2020/21 | Fortuna Düsseldorf · 5th | 2 | 0 | 0 | — | 54 | 0 |
Domestic-league totals per season. RTG = Field Insider Rating (potential / ceiling); Season = age-blind form that year.
J. Siebert is a 24-year-old central defender at Lecce, rated 70 overall by Field Insider's model, ranking 159th of 389 in the Serie A. An emerging talent, he has been a rotation option this season (49.9% of available minutes). His defensive output reads 3.32 tackles, blocks and interceptions per 90. Below: strengths, watch-points, market-value outlook and the latest transfer news on Siebert.
Judged on this season alone, Siebert graded 24 — a workmanlike campaign that ranks 43rd of 52 of the 52 centre-backs in the Serie A, on 5 clean sheets and 3.322 defensive actions per 90.
Year-on-year, that's broadly in line with last season (Season 26 → 24). Over the 6 seasons on record his form has trended upward, peaking in 2023/24.
On long-term talent our Rating reads 70, top 39% of the 52 centre-backs in the Serie A. At 24 Siebert is in his prime years, and a market index of 43.3 reflects that trajectory.
Below his 2023/24 peak but holding a solid level — the platform for a return is there.
3.32 tackles, blocks & interceptions per 90 — moderate defensive volume, with 5 clean sheets across 21 appearances. Doing that for a lower-table side (17th of 20) is harder than the bare numbers suggest: a back line under more pressure has to defend more often and protects fewer leads, so the volume — and any clean sheets — carry real weight. Going forward he chipped in 1 goal and 0 assists — a useful bonus from the back.
With a Rating of 70, Siebert carries the 20th-highest potential of the centre-backs in the Serie A (top 39%), and he is posting that for a lower-table side (Lecce finished 17th of 20) — individual numbers are harder to earn on a struggling team, so his underlying level likely sits a touch above the ranking. Defensively he reads as moderate defensive volume (3.32 tackles, blocks & interceptions per 90). Approaching peak years; value is still building (price multiplier 2×) with the best seasons likely ahead. Doing it for a lesser side, he profiles as a value buy for a club higher up the table.
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 (~43), then tapers with age. At 24, Siebert sits on 43.3, at or near its peak. The blue line is Siebert's projected Rating — 70 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.