Just a few months ago, Mateo Biondic was playing for Eintracht Trier in the Regionalliga Südwest and struggling with repeated injuries; now he’s on the verge of winning his first title in Belgium with Union Saint-Gilloise. Contrary to expectations, he’s playing a starring role right from the start.
At the beginning of this year, his transfer caused a sensation across Germany: “From the Regional League to the Champions League” was the headline in many places when Mateo Biondic moved from fourth-division side Eintracht Trier to Belgian champions Union Saint-Gilloise. Comparisons with national team striker Deniz Undav, who had once moved from Meppen to the Brussels suburb and made a name for himself there, quickly emerged.
Biondic contributed seven goals and five assists in 17 games for SVE in the first half of the season; his sale brought a record transfer fee of more than 200,000 euros into the former second-division club’s cash-strapped coffers. Without its key offensive player, Eintracht’s engine is now running at a snail’s pace. Thomas Klasen’s team has managed just eleven goals in 13 league games since the turn of the year. For Biondic, meanwhile, the move has paid off: he has quickly become a key figure in the offense at his new club, even though he was not yet eligible to play in the Champions League in January due to a missed registration deadline. This wasn’t necessarily expected, any more than his rapid rise in Trier had been.
Several second-division clubs were also vying for Biondic
In the winter, the Belgians weren’t the only ones interested in Biondic following his strong first half of the season: Several German second-division clubs, such as 1. FC Nürnberg—which, like Union, uses data-driven scouting with Jamestown Analytics—are also said to have been interested in the physically strong and versatile forward. Trier’s sporting director Daniel Hammel saw the move to a higher level at the time as the logical next step: “Based on his performance data and development, it was clear early on that Mateo’s path would lead to professional soccer and that he wouldn’t stay at Eintracht Trier for long.” In the meantime, the first Bundesliga clubs are said to have already inquired about the rising star at the club, which won the championship in 2025 for the first time in 90 years.
In Belgium, Biondic has also benefited so far from injuries to other players. Canadian national team player and top striker Promise David has been out since February, Austrian Raul Florucz was sidelined for about two months, and with Kevin Rodriguez, another competitor was injured in March. At some point, Biondic was virtually the only one left—and he immediately impressed coach David Hubert. Initially called upon as a substitute, the 22-year-old scored his first goal in his starting lineup debut against FCV Dender EH (2-0) in March. Since then, he has been a regular at Saint-Gilles, sometimes as a center forward, sometimes as a right winger.
A pivotal week for Saint-Gilles
Just this past weekend, Biondic was once again the decisive player in the 3-0 victory over Mechelen in the championship round: scoring the 1-0 goal and assisting on the 2-0. “All glory to Jesus,” the devout Christian thanked—as usual—after the match on DAZN. He had missed the previous two games due to a broken arm, and the German-Croatian played against Mechelen with a cast. “My arm is broken, I had surgery, and I got married,” Biondic said of his wedding three days earlier in his hometown of Trier. “The last two weeks have been the highlight so far.”
At least on the sporting front, the next highlights are already coming up this week: On Thursday, Union faces Anderlecht in the cup final, and three days later, they travel to Club Brugge on the third-to-last matchday. First against second; Brugge holds a one-point lead. In the first leg about a month ago, Saint-Gilles prevailed 2-1. The scorer of the equalizer to make it 1-1: Biondic. Now the decisive match for the championship awaits—likely with Biondic playing a key role.
Two difficult first years in Trier
A year ago, his situation looked quite different. Flashback to May 2025: After 13 winless games, Eintracht Trier barely managed to avoid relegation in the Regionalliga, despite a 1-2 loss in front of an empty stadium against Frankfurt II, who had already been relegated. In his second season in Trier, Biondic never really found his stride; due to various muscle injuries and hip flexor issues, he was frequently sidelined for the fourth-division promoted side and only played a role again in the final stretch of the season. Biondic, who was trained at Schalke, Hannover, and SC Paderborn, scores a meager one goal in 20 games; while he repeatedly hints at his potential during his appearances, he proves too inefficient in front of the goal.
In the 2023/24 Oberliga season, after a strong start with Eintracht, Biondic missed the entire second half of the season due to a torn Achilles tendon. Consequently, his parent club SC Verl extended his loan to Trier for another season; despite health setbacks, he is well integrated on the Moselle and is also involved as a youth coach.
Rapid rise in the first half of the season
However, Biondic’s originally planned return to East Westphalia—where he had already made his third-division debut in July 2022 at age 19 in a match against 1. FC Saarbrücken (0–1) and appeared five times in the third division during the first half of the season—will no longer take place. In Trier, the forward signs a two-year contract in the summer of 2025.
He won’t fulfill this one either: In a very short time, he transforms from a part-time player into a lifeline for the team and, with his versatility, increased efficiency, and full commitment, makes a decisive contribution to what is supposed to be the team’s next step. “I can now enjoy the development,” says Biondic, who had previously always been sidelined, during the first half of the season on the club’s own podcast. At this point, even he has no idea that this will propel him even higher so quickly.