According to Index.hr, Lokomotiva has signed 22-year-old Croatian forward Mate Antunović from Varaždin. Antunović began his football career at Jadran Luka Ploče and later moved to Hajduk's youth academy, where he played in the UEFA Youth League final with the junior team. During his career, he has played for Hajduk, Monza, Varaždin, and Dugopolje, and has also been a Croatian U-21 national team player. Last season, he played in 23 official matches and scored three goals. After signing, Antunović stated that his personal goal is to progress and score goals in the Lokomotiva jersey and that he is looking forward to the matches starting.

Dalmatinski portal reported that Croatian centre-forward Mate Antunović, aged 22, has mutually agreed to terminate his contract with Varaždin and is set to continue his career at Lokomotiva. The forward joined Varaždin in January 2025 and spent the second half of last season on loan at second-division club Dugopolje. He had a contract with Varaždin that was valid until the summer of 2027. According to Dalmatinski portal, Lokomotiva's coach Nikica Jelavić wanted Antunović to increase competition within the attack. In the 2025/2026 SuperSport HNL domestic league, Antunović made 28 appearances and scored 1 goal. The Croatia U21 international has 4 caps and 1 goal for his country and a current Transfermarkt market value of €300k.