Bundesliga club Mainz 05 has submitted an initial offer for 19-year-old midfielder Sung-jun Yoon of Kyoto Sanga. There is no information about the amount of the offer. Information emerged two weeks ago that Mainz were interested in the young South Korean. Yoon, who joined Kyoto Sanga in August 2025, has a contract with the club until June 30, 2029, and his current market value is estimated by Transfermarkt to be €400k.