Borussia Dortmund have signed Konstantinos Karetsas from Genk in Belgium, with the highly rated Greece international teenager penning a long-term contract until June 2031. Dortmund managing director of sports Lars Ricken said: "With Kos, we’re adding a player to Borussia Dortmund who, at just 18 years old, already possesses tremendous talent. The left-footed attacking midfielder was born in Genk and came through at his hometown club, also having a spell in Anderlecht’s academy between 2020 and 2023. He made his debut in Belgium’s second division as a 15-year-old with Jong Genk and then his top-tier debut at 16 years and eight months in July 2024. Karetsas said: “Borussia Dortmund is a special club, and I’m incredibly proud to now be able to wear the Black and Yellow jersey.