Oskar Fallenius is approaching the end of his contract with Djurgarden and has spoken about a potential free transfer in January. The 24-year-old is due to become a free agent at the end of the calendar year, which could alert Celtic and other interested clubs. Fallenius was first linked with Celtic last summer, and more recent reports in Sweden claimed he had also been considered by Martin O’Neill. Despite being widely expected to leave Djurgarden this summer, the winger remained in Sweden. In an interview with Sportbladet, Fallenius said he finds it difficult to believe he could move to a country where the transfer window remains open. He stated that he has planned to stay until his contract expires, at which point they will decide on the next steps. Discussing his future, he added that he has a wide range of options and has ambitions. Fallenius said that after three and a half years at the club he thinks he will have a clear understanding of the situation after the season, and they will determine what is best for him and Djurgarden.

According to Sport Witness, citing a report from Sweden, Celtic showed great interest in Oskar Fallenius in May 2025. Celtic were reportedly interested again in the last window. Brøndby, which retains a 15% sell-on clause, were disappointed that Oskar Fallenius did not join Celtic in the summer. His contract with Djurgårdens IF expires in December, and based on the current situation, he will join a new club in January on a free transfer. Celtic is mentioned as a club that has to convince him with its sporting project and by offering a good financial package, as no transfer fee will be required for the signing.

Rangers are considered likely to sign Djurgarden winger Oskar Fallenius ahead of Celtic. Fallenius is a 24-year-old Swede who is expected to leave the club this summer. The player's manager, Jani Honkavaara, has admitted a departure is inevitable if a suitable offer is made. While Celtic's interest appears to have recently diminished, Rangers may now have competition from other European clubs, as Bundesliga side Wolfsburg is also reportedly tracking him. Fallenius, who has not yet been capped by Sweden, has a contract until the end of 2026 and has provided one assist in six Allsvenskan appearances this season. He joined his current club in February 2023 for a reported €175,000, and his current Transfermarkt market value is €400,000.