Borussia Dortmund's €20 million offer for Polish defender Kacper Potulski rejected by Mainz

Borussia Dortmund submitted a transfer bid of €20 million for 18‑year‑old Polish international centre‑back Kacper Potulski. The offer was immediately turned down by his current club, FSV Mainz 05, which indicated it expects a higher fee.

Potulski, who has featured in 15 Bundesliga matches for Mainz and scored in a friendly against Nigeria, is valued at about €18 million on Transfermarkt. His contract runs until June 2028. Besides Dortmund, clubs such as Bayern Munich, Bayer Leverkusen, AC Milan, Inter Milan and several Premier League teams have been reported to monitor his situation.