Mainz 05 linked with Sung-jun Yoon as Sano replacement – offer details emerge

1. FSV Mainz 05 has taken concrete steps to fill the void left by the potential departure of Kaishu Sano. The Japanese international is being courted by multiple top clubs, including Premier League sides. The Rheinhessen outfit has now tabled a first offer for 19-year-old midfielder Sung-jun Yoon from Kyoto Sanga in Japan’s top flight.

What happened?

According to Japanese sports daily Sports Hochi, Mainz 05 submitted an initial bid for Yoon, though the exact financial terms have not been disclosed. The South Korean is viewed as one of Asia’s brightest prospects and could replace Sano if the 25-year-old Japan international leaves. Reports suggest Sano’s release fee is around €60 million.

Talks remain at an early stage and other clubs, including Eintracht Frankfurt and Bayer Leverkusen, are also tracking Yoon. Mainz must move swiftly to avoid losing out on a player who could bolster their attack.

Why it matters for Mainz 05

Sano has been a key figure for the club, contributing 10 goals and eight assists last season. His potential exit would leave a major void, especially in attack. Yoon’s technical ability and game intelligence make him a strong candidate to step into that role.

With Mainz sitting 10th in the Bundesliga on 40 points from 34 games at the end of the 2025 campaign, every point counts. A signing like Yoon could help push the team’s ambitions for the new season.

What’s next?

Negotiations between Mainz 05 and Kyoto Sanga are ongoing. Yoon’s move depends on several factors: the size of the bid, the player’s willingness and any counter-offers. The club is pushing for a quick resolution to shore up the squad ahead of the new campaign.

Fans are hoping for a reinforcement who can soften the blow of Sano’s departure. Should Yoon arrive, it would be a significant step for the club’s future. The coming weeks will determine whether Mainz can get the deal over the line.

Mainz 05 finished the 2025 season 10th in the Bundesliga with a record of 10 wins, 10 draws and 14 losses, and are currently on a two-game winning streak following the 2:0 victory over Heidenheim on 16 May 2026.