Transfermarkt has identified Bosnian winger Kerim Alajbegović as the youngest and most expensive under 21 transfer in Europe’s top leagues this summer. The distinction highlights the growing value of teenage talent in the European transfer market. The 18 year old joined Juventus from Bayer Leverkusen in early August for a total package reported at €37 million, putting him at the top of Transfermarkt’s ranking of players under 21 who moved to Serie A this summer.
Alajbegović ranks ahead of 20 year old Oulai and 21 year old Aleksandar Stanković on the list. Across Europe’s major leagues, only 19 year old Diomandé, who moved from Leipzig to Real Madrid for €125 million, joined Alajbegović as a teenager among the 25 most expensive transfers of the summer. The figures underline just how highly leading clubs value young players who have already gained senior level experience.
Alajbegović’s Rapid Rise to Juventus
Alajbegović’s rise has been remarkably quick. Born in Cologne to Bosnian parents, the two footed winger developed in the youth system at 1. FC Köln before joining Bayer Leverkusen in 2021. After signing his first professional contract in January 2025, he moved on loan to Red Bull Salzburg, where he made 44 appearances across all competitions, scoring 13 goals and providing four assists.
Leverkusen activated an €8 million buyback clause in March 2026 following his strong performances, but Juventus quickly moved ahead of Chelsea and other interested clubs. The Italian side agreed to an initial €33 million transfer fee that could reportedly rise to €40 million with add ons. Juventus then handed the teenager a five year contract running until June 2031, making a significant investment in his long term potential.
What makes Alajbegović’s transfer particularly notable is the level of his development at such a young age. He made his senior debut for Bosnia and Herzegovina in September 2025 and quickly established himself at international level, collecting 11 caps and scoring twice. His performances have helped turn him into one of the most closely watched young Bosnian players in European football.
Transfermarkt’s specialized agents portal reported that Alajbegović’s market value had climbed to €25 million by the time of his move to Turin. That represented a substantial increase from the €8 million valuation he carried in March after only half a season of senior football. His rapid rise has made him a reference point for clubs and agents monitoring the next generation of elite talent.
The transfer also reflects a broader shift in European football, with major clubs increasingly willing to pay substantial fees for teenagers who have already demonstrated their ability at senior and international level. While Diomandé’s nine figure move to Madrid dominated the headlines, Alajbegović’s €37 million switch is notable because he had not yet played a Bundesliga match for Leverkusen before leaving the club.
Juventus is betting that Alajbegović’s experience at Salzburg and on the international stage has prepared him for the demands of Serie A. With his 19th birthday not arriving until September 21, the teenager has already established himself as one of the defining young transfers of the 2026 summer window.
