Jae-Sung's current-season form is level with last season (Season 27→27), while his Rating held around 26. His peak season for form remains 2024/25 (Season 48).

Domestic career

Season	Club	Apps	G	A	Match	RTG	Season
2026/27	FSV Mainz 05 · 8th	3	0	1	6.47	26	27
2025/26	FSV Mainz 05 · 10th	28	4	2	6.68	26	27
2024/25	FSV Mainz 05 · 6th	33	7	6	7.16	47	48
2023/24	FSV Mainz 05 · 13th	29	6	3	7.03	47	36
2022/23	FSV Mainz 05 · 9th	34	7	4	6.96	53	40

Domestic-league totals per season. RTG = Field Insider Rating (potential / ceiling); Season = age-blind form that year. 8 earlier seasons in the full career.

Korea Republic · international

Side	Apps	G
Korea Republic U23	7	0
South Korea	107	15

Career caps & goals — tournament breakdown in the full career.

Scout report

Experienced headAttacking midfielder

Lee Jae-Sung is a 34-year-old attacking midfielder at FSV Mainz 05, enjoying a standout season — 4 goals and 2 assists in 28 appearances, a Season grade of 27. On long-term scout potential he's rated 26.3. A seasoned veteran, he has been a regular starter (71.8% of available minutes). He brings 0.25 goal contributions per 90 (0.16 goals, 0.08 assists). Below: strengths, watch-points, market-value outlook and the latest transfer news on Jae-Sung.

On the season, Jae-Sung graded 27 for current form (age-blind), on 4 goals and 2 assists in 28 appearances (0.246 involvements per 90).

Year-on-year, that's broadly in line with last season (Season 27 → 27). Over the 7 seasons on record his form has drifted down, peaking in 2024/25.

On long-term talent our Rating reads 26. At 34 Jae-Sung is into the veteran stage, where the age curve weighs on the projection, and a market index of 7.9 reflects that trajectory.

From the career report

Read the full career report →

Past his 2024/25 peak — the recent trend is downward, so buyers are paying for what's left, not what was.

Peak: 2024/25Trending downStepped up 2021/22Injury-hit 2025/26

26.3

Ratingi

below regular-starter level

27.4

Seasoni

below regular-starter level

71.8%

Minutes

a regular starter

0.25

Goal contrib / 90

modest end product

Output in context · FSV Mainz 05 finished 10th of 18 · a mid-table side

Apps

Goals

Assists

G+A

0.14

Goals / app

4 goals in 28 appearances (0.14 per game) — light end product the role wants to see climb. Add 2 assists for 6 goal contributions in all.

Strengths

Availability. On the pitch for 71.8% of available minutes — a dependable presence in the XI.

Watch points

Output. 0.25 contributions per 90 is light for an attacking role — end product needs to climb.
Age curve. At 34, both level and resale value are on the downslope.
Level. Rates below a nailed-on top-tier starter on our model.

Outlook

Rated 26.3 overall — below regular-starter level. In the final third he profiles as a work-in-progress on end product (0.25 goal contributions per 90). Veteran phase — a short-term, lower-fee proposition as both level and value decline (0.6× and falling).

Generated from Field Insider's rating model · AI-written analysis to follow.

Per 90 & availability

Minutes played %71.8%

Available fixtures34 of 34

Goals / 900.164

Assists / 900.082

Goal contribution / 900.246

Defensive actions / 902.621

Player flow

Goal involvements6

Cards / 900.164

Season-by-season progression

Rating (potential)Season (form)

Value & potential by age

Market valueRating

Solid = now · dashed = projected

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 (~26), then tapers with age. At 34, Jae-Sung sits on 7.9, past its peak and easing. The blue line is Jae-Sung's projected Rating — 26.3 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.

Season statistics

Bars = where he ranks among attacking midfielders in the Bundesliga with 600+ minutes this season.

Shooting

Goals4

Passing

Assists2

Defending

Tackles38

Interceptions25

Blocks1

Yellow/red cards

Yellow cards4

Red cards0

Transfer history

€1M total transfer fees · 2 moves

FSV Mainz 05Jul 2021 – nowFree

Holstein KielJul 2018 – Jul 2021€ 1M

Jeonbuk Motorsuntil Jul 2018

About Lee Jae-Sung

Jae-Sung Lee is a 34-year-old attacking midfielder who plays for FSV Mainz 05, born on August 10, 1992 in Ulsan, standing 180 cm tall. He is from Korea Republic. FSV Mainz 05 currently sit 8th of 18 in the Bundesliga.

This season

In the current season, Lee Jae-Sung has made 3 appearances with 0 goals and 1 assist across 201 minutes, averaging a 6.55 match rating over his last 3 rated games. His season has spanned the World Cup - Qualification Asia, the Friendlies and the World Cup.

Recent matches

September 12, 2026: 1-3 loss at home vs Eintracht Frankfurt (45 minutes, 5.81 rating)
September 6, 2026: 5-0 win away at Hamburger SV (88 minutes, 1 assist, 7.54 rating)
August 29, 2026: 0-0 draw at home vs SC Paderborn 07 (68 minutes, 6.3 rating)

Lee Jae-Sung's next match is on September 19, 2026, when FSV Mainz 05 face Borussia Mönchengladbach away in the Bundesliga.

Field Insider's view

Field Insider currently rates Lee Jae-Sung at 26.3 with a Season form score of 27.4. See the full scout report for strengths, watch-points and the market-value outlook.

His honours include 11 career titles — among them the K League 1 and the EAFF E-1 Football Championship. Full list in the career record.

Career

Across 13 recorded seasons, Lee Jae-Sung has totalled 384 club appearances with 73 goals and 36 assists for 3 different clubs. His busiest campaign came in 2015/16, with 34 appearances for Jeonbuk Motors.

Lee Jae-Sung's career has also included time at Holstein Kiel and Jeonbuk Motors.

On the international stage, Lee Jae-Sung has represented Korea Republic U23 and South Korea — 114 caps and 15 goals in our records.

Transfer news

No transfer news found for this player.