PLAYER SNAPSHOT: At a Glance
| Category | Details |
|---|---|
| Full Name | Lee Jae-sung (이재성) |
| Date of Birth | 10/08/1992 (Age: 33) |
| Place of Birth | Ulsan, South Korea |
| Nationality | South Korean |
| Height | 1.80 m / 5 ft 11 in |
| Weight | — |
| Position | Midfielder (Attacking/Central) |
| Preferred Foot | Left |
| Squad Number | #7 |
| Current Club | Mainz 05 |
| Previous Clubs | Jeonbuk Hyundai Motors, Holstein Kiel |
| International Caps | 107+ |
| International Goals | 15 |
| World Cup Appearances | 2018, 2022, 2026 |
| Contract Until | — |
| Market Value | — |
The Frozen Moment
The 2026 FIFA World Cup in Mexico was always going to be Lee Jae-sung’s farewell. The 33-year-old midfielder, who had worn the South Korean badge over 100 times across a distinguished international career, had made the decision months before the tournament began: this would be his last dance.
“I think this will be my final World Cup as a player,” Lee told reporters before a training session in Utah. “You just never know when you will have another opportunity like this. Every player here is not thinking about the next World Cup. We are all concentrating on this year’s World Cup.”
The announcement carried weight. Lee had been a quiet hero of Korean football for over a decade—never flashy, never seeking the spotlight, but always present. As one commentator observed, “people often say that wherever the ball is, Lee Jae-sung is there.” His fighting spirit and work rate were exceptional, yet he had often remained a supporting figure rather than the main character.
Just months before the tournament, Lee had suffered a toe fracture, an injury that threatened his participation. But his remarkable resilience—the same resilience that had defined his career—carried him through to recovery. Now, standing on the world’s biggest stage for the third time, Lee Jae-sung was ready to embrace the nerves, embrace the pressure, and finally step into the spotlight.
Origins
Born on August 10, 1992, in Ulsan, South Korea, Lee Jae-sung’s football journey began at Korea University, where he studied and developed his game from 2011 to 2014. It was at university that his talent matured and attracted the attention of professional clubs.
His professional debut came on February 26, 2014, when he represented Jeonbuk Hyundai Motors in the AFC Champions League against Yokohama F. Marinos. This marked the beginning of a career that would span over a decade at the highest levels of Asian and European football.
Lee’s international career began on March 27, 2015, when he made his senior debut for South Korea. His first international goal came soon after, on March 31, 2015, in a 1-0 friendly victory over New Zealand at the Seoul World Cup Stadium.
The Global Journey
Jeonbuk Hyundai Motors (2014-2018):
Lee established himself at Jeonbuk Hyundai Motors, winning multiple K League titles and becoming a key figure in the club’s midfield. His performances earned him a reputation as one of Korea’s most promising playmakers, and in the 2017 EAFF Championship, he led South Korea to victory and was named both the tournament’s Most Valuable Player and Best Duel Player.
Holstein Kiel (2018-2020):
Lee’s European adventure began with a move to Holstein Kiel in the 2. Bundesliga. His time in Germany was a transitional period, allowing him to adapt to European football while maintaining his international form.
Mainz 05 (2020-Present):
Lee joined Mainz 05 in the Bundesliga and has since become a pillar of consistency in the Zerofivers’ midfield. Over five seasons, he has made 151 top-flight appearances, scoring 28 goals and providing 19 assists. His Bundesliga career has seen him rise to become the third-highest Korean goalscorer in Bundesliga history, trailing only Cha Bum-kun and Son Heung-min.
The 2025-26 season was a particularly successful one. After a tricky start under a new regime, Lee and his Mainz colleagues soared up the Bundesliga table following Urs Fischer’s appointment as head coach in December. They finished the campaign in 10th spot and reached the quarter-finals of the UEFA Conference League—the first European quarter-final in the club’s history. Lee scored six goals across all competitions in 2025-26, registered four assists, and logged more intensive runs than all but two of his teammates, a testament to his relentless work rate.
One of his most memorable moments came in Fischer’s first game in charge, when Lee netted a perfectly timed header to give Mainz the lead in an eventual 2-2 draw at Bundesliga champions Bayern Munich. He also scored a dramatic last-minute winner in a 2-1 Conference League victory over Fiorentina.
The Anatomy of His Game
Lee Jae-sung is a playmaking midfielder who combines tactical intelligence with exceptional work rate. His game is defined not by flashy skills but by his constant presence, his ability to read the game, and his remarkable aerial ability for a midfielder.
In Possession:
Lee is a creative force from central midfield, capable of creating chances for forwards and wingers. In the 2025-26 Bundesliga season, he recorded a pass completion rate of 71.4% and created 24.3 chances per 90 minutes across 28 appearances. His versatility allows him to play in multiple midfield roles—from attacking midfielder to defensive midfielder alongside a partner like Hwang In-beom. “In-beom is such a great player, and since we’ve played together on the national team for so long, we already know how the other likes to play,” Lee said of his midfield partnership.
Out of Possession:
Lee’s work rate is exceptional. He logged 1,943 intensive runs in the 2025-26 Bundesliga season—more than any other Mainz player apart from Paul Nebel and Kaishu Sano. His defensive contributions include 25 tackles in Bundesliga matches. Coaches praise his relentless energy; Mainz boss Urs Fischer noted, “With Lee, he sometimes needs protecting from himself. He can play three times a week with no issues whatsoever.”
Aerial Ability:
One of Lee’s most distinctive attributes is his heading ability. Of his 28 Bundesliga goals, 12 have come from headers. As Lee himself explains, “My biggest strength is my diligence, and scoring headers ultimately comes from finding space and making runs into it.” This aerial threat has made him a valuable attacking weapon.
Psychological Edge:
Lee’s quiet professionalism has defined his career. He has been described as “the engine of Korean football, a quiet hero.” Despite his soft-spoken demeanor, he has accumulated over 100 caps and has been a constant presence in South Korea’s midfield for a decade. His decision to announce his retirement before the World Cup reflects his commitment to focusing on the present: “I think I will get even more nervous as we get closer to the tournament, because I know how precious and how important this opportunity is.”
The Numbers Game
TABLE A: The Data Snapshot (2025/26 Season)
| Competition | Apps | Starts | Minutes | Goals | Assists | Pass Accuracy | Rating |
|---|---|---|---|---|---|---|---|
| Bundesliga (Mainz) | 28 | 26 | 2,185 | 4 | 2 | 71.4% | 6.42 |
| UEFA Conference League | 9 | — | 507 | — | — | — | — |
| FIFA World Cup 2026 | — | — | — | — | — | — | — |
| TOTAL | 37 | 26 | 2,692 | 4 | 2 | — | — |
TABLE B: Career Overview
| Season(s) | Club | League/Competition | Apps | Goals |
|---|---|---|---|---|
| 2014-2018 | Jeonbuk Hyundai Motors | K League | — | — |
| 2018-2020 | Holstein Kiel | 2. Bundesliga | — | — |
| 2020-Present | Mainz 05 | Bundesliga | 151 | 28 |
| TOTAL | — | — | 151+ | 28+ |
TABLE C: International Record
| Tournament/Competition | Apps | Minutes | Goals | Major Honours |
|---|---|---|---|---|
| FIFA World Cup 2018 | 3 | 270 | 0 | Group Stage |
| FIFA World Cup 2022 | — | — | — | Round of 16 |
| FIFA World Cup 2026 | — | — | — | Group Stage |
| EAFF Championship 2017 | — | — | — | Winner |
| South Korea Senior Career | 107+ | — | 15 | — |
TABLE D: Career Milestones
| Year | Achievement | Details |
|---|---|---|
| 2014 | Senior Debut | Jeonbuk Hyundai Motors |
| 2015 | Korea Debut | Senior international debut |
| 2015 | First International Goal | vs New Zealand |
| 2017 | EAFF Championship Winner | South Korea |
| 2017 | EAFF Championship MVP | South Korea |
| 2018 | World Cup Debut | Russia 2018 |
| 2018 | Holstein Kiel Transfer | Move to Germany |
| 2020 | Mainz 05 Transfer | Bundesliga debut |
| 2022 | World Cup Appearance | Qatar 2022 |
| 2025 | 100th International Cap | vs Brazil |
| 2026 | World Cup Appearance | Third World Cup |
These figures reveal a player of remarkable consistency and durability. Lee has accumulated over 150 Bundesliga appearances, scored 28 goals, and earned 107 caps for South Korea—placing him on the brink of the top 10 appearance-makers in Korean football history. His 15 international goals, including five in qualifying for the 2026 World Cup, demonstrate his continued importance to the national team.
The Present Tense
The Mainz Story:
Lee has been a pillar of consistency for Mainz since joining in 2020. The 2025-26 season saw him make 28 Bundesliga appearances, scoring four goals and providing two assists. Under head coach Urs Fischer, Mainz finished 10th in the Bundesliga and reached the Europa Conference League quarter-finals—the first European quarter-final in the club’s history. Lee was a key contributor, scoring a dramatic last-minute winner against Fiorentina and logging the third-most intensive runs in the squad.
The FIFA Club World Cup:
Lee has not yet featured in a FIFA Club World Cup. Mainz have not qualified for the tournament during his tenure, though their improved European performances position the club for future success.
The World Cup Campaign:
The 2026 FIFA World Cup in the United States, Canada, and Mexico marked Lee’s third appearance at the tournament. He was named in Hong Myung-bo’s 26-man squad and was expected to play a central role in midfield. Lee had previously played every minute of South Korea’s group campaign at the 2018 tournament before helping them reach the round of 16 four years later.
International Record:
Lee has accumulated 107 caps for South Korea since his debut in 2015, scoring 15 goals. He has been a constant presence in the national team setup, featuring in three FIFA World Cups, the 2017 EAFF Championship (which South Korea won, with Lee named MVP), and numerous qualifying campaigns. In 2025, he made his 100th international appearance in a friendly against Brazil. His performances in qualifying for the 2026 World Cup included five goals.
Current Status:
Lee has announced that the 2026 World Cup will be his final appearance as a player. He has been recovering from a toe fracture suffered in May 2026 but was expected to be fit for the tournament. His commitment to the national team has been unwavering: “Our biggest goal is to stick around as long as we can. This is a privilege that only the countries that qualified for the World Cup can enjoy, and we want to share this with our people back home.”
Beyond the Touchline
Off the pitch, Lee Jae-sung is known as a quiet professional who lets his performances speak for themselves. He has been described as the “engine of Korean football, a quiet hero.” His style may not be flashy, but his fighting spirit and work rate are exceptional. “People often say that wherever the ball is, Lee Jae-sung is there.”
Lee’s career has been punctuated by significant achievements. He has won multiple K League titles with Jeonbuk Hyundai Motors, the EAFF Championship with South Korea (where he was named MVP), and has established himself as the third-highest Korean goalscorer in Bundesliga history. He has over 150 Bundesliga appearances to his name and has represented his country in three World Cups.
His friendship with captain Son Heung-min has been a constant throughout his career. The two were among the most experienced players in the 2026 World Cup squad. “He has been my biggest source of strength over the years,” Lee has said of Son, though he added that he felt this World Cup would be his own personal farewell.
The Verdict from the Camp
Urs Fischer, Mainz Head Coach:
“With Lee, he sometimes needs protecting from himself. He can play three times a week with no issues whatsoever.”
Hong Myung-bo, South Korea Head Coach:
“He can play in any role. He is a very gifted player.”
Statistic:
Lee is the third-highest Korean goalscorer in Bundesliga history, following Cha Bum-kun and Son Heung-min.
Statistic:
Lee has accumulated 107 caps for South Korea, placing him on the brink of the top 10 appearance-makers in Korean football history.
Statistic:
Lee scored five goals in qualifying for the 2026 World Cup.
Statistic:
Lee has scored 28 Bundesliga goals, with 12 coming from headers.
Where Next?
Lee Jae-sung is 33 years old and has announced his retirement from international football after the 2026 World Cup. His future at club level remains uncertain, though his contract with Mainz 05 and his continued Bundesliga form suggest he could continue in Germany or potentially move elsewhere.
For South Korea, Lee’s retirement will represent the end of an era. His 107 caps, three World Cups, and 15 international goals have made him one of the most influential midfielders of his generation. His replacement will be a significant task for the new head coach, whoever that may be following Hong Myung-bo’s resignation after South Korea’s group-stage exit.
From the youth fields of Korea University to the grand stages of the FIFA World Cup and the Bundesliga, Lee Jae-sung’s journey is one of quiet dedication, relentless work rate, and unassuming excellence. The midfielder who has always been there—wherever the ball is—has finally stepped into the spotlight.
