Ivan Kolarik, a 19-year-old Croatian centre-back, has been capped once for the Croatia U19 team and joined Osijek in July 2025 on a contract to June 2029. Porto and Dinamo Zagreb have previously been linked with the player. In June 2026, reports indicated Osijek was asking for approximately €1.5 million. His current market value is estimated by Transfermarkt to be €300,000. Osijek's sporting director, Kenneth Zandvliet, commented that there is great interest from abroad for Kolarik. Zandvliet stated that Osijek does not plan to let Kolarik go and that the offer must be right for them to release him. He said any offer for Kolarik must be serious. Zandvliet emphasized that Kolarik has everything needed to become a great player, is improving with each match, fits their style of play, and will not be released easily.