Mateo Biondic

Mateo Biondic's route to a UEFA Champions League club began in the German fourth tier, a rise the club's own press has compared to Deniz Undav's trajectory. He spent his youth years at TBV Lemgo, Hannover 96, Schalke 04 and SC Paderborn 07, then moved through Paderborn's second team and a free transfer to SC Verl before joining Eintracht Trier on loan in 2023. His first season there brought seven goals in 21 Oberliga appearances, cut short by a torn Achilles tendon. The following campaign was disrupted again, this time by muscle and hip flexor problems, limiting him to a single goal in 20 matches. He signed for Trier permanently in June 2025.

The breakthrough came in the 2025–26 Regionalliga season, when Biondic scored seven goals and added five assists in 17 matches. The form prompted Union Saint-Gilloise to sign him in January 2026, a rare jump from Germany's fourth division straight into the Belgian Pro League and a record transfer fee for Trier. At Union, he has made 18 appearances and scored five goals in the league this season.

Off the back of his wedding in March 2026, Biondic broke his arm and needed surgery, only to return in a cast against Mechelen, where he scored the opening goal and set up another. He was on the pitch when Union won the Belgian Cup, beating RSC Anderlecht 3–1 after extra time on 14 May 2026, with the goals coming from Mac Allister, Cvetković and Fuseini.

Biondic holds dual German and Croatian nationality and previously featured for Croatia's youth teams, though he has yet to win a senior cap for either country.