By Lizzy Becherano The Chicago Fire have signed midfielder Gaston Gimenez to a new contract, opening up a Designated Player slot on the roster ahead of the 2023 MLS campaign. The 30-year-old’s new deal kicks off in January, extending his time at the club through the 2025 season. The Paraguay international also received his U.S. Green Card earlier this year and will no longer occupy an international roster slot. “Gaston is a talented player who is very important to the club,” Chicago sporting director Georg Heitz said in a release. “His decision to restructure his contract to provide the team w…