Bundesliga World Cup Stars: Mainz’s Jae-sung Lee

Jae-sung Lee enters the FIFA World Cup 2026 as one of South Korea’s most dependable and in-form players after an impressive second half of the 2025/26 season with Mainz. The 33-year-old midfielder helped transform Mainz following the appointment of Urs Fischer last December, as the club recovered from a difficult start to finish 10th in the Bundesliga and reach the UEFA Conference League quarter-finals, the first European quarter-final in Mainz’s history.

Lee was a key figure in that resurgence, appearing in every league match he was available for and providing consistency, energy and attacking quality from midfield. He made an immediate impact under Fischer, scoring a well-timed header in the coach’s first game in charge to put Mainz ahead in a 2-2 draw away to Bayern Munich. He also produced one of the club’s standout moments of the season when he scored a dramatic late winner against Fiorentina in the Conference League league phase in November. Across all competitions, Lee finished the campaign with six goals and four assists, underlining his influence in both build-up play and decisive moments.

Beyond his goals and creativity, Lee’s work rate was a major asset for Mainz. He recorded 1,943 intensive runs during the season, ranking among the team’s most industrious players and highlighting the relentless movement that made him so valuable in Fischer’s system. His reliability, versatility and tactical discipline helped Mainz maintain momentum during their strong finish to the season.

Lee now carries that form into international duty with South Korea, where he has become a senior and trusted presence. He made his debut on 27 March 2015 and, as of 11 June 2026, has earned 105 caps and scored 15 goals. Those numbers place him close to South Korea’s top 10 all-time appearance-makers. He is also one of the more experienced players in Hong Myung-bo’s World Cup squad, second only among outfield players to Heung-min Son in age.

At previous World Cups, Lee has already shown he can perform on the biggest stage. He played every minute of South Korea’s group stage in 2018 and helped the team reach the round of 16 in 2022. His experience, combined with his goal threat, makes him an important figure for South Korea’s hopes at the tournament in Canada, Mexico and the United States. Notably, five of his 15 international goals have come in World Cup qualifying, further demonstrating his value in high-pressure matches.

South Korea coach Hong Myung-bo has praised Lee’s versatility and quality, noting that he can play in multiple roles and may be deployed alongside Hwang In-beom in central midfield. Fischer has also highlighted Lee’s exceptional fitness and durability, saying he can handle a heavy match schedule without issue. That combination of technical ability, stamina and experience means Lee is expected to be a central part of South Korea’s plans at the 2026 World Cup.