Olympiacos submitted an offer of approximately €12,000,000 for 24-year-old Brazilian defensive midfielder Mateus Martinelli, which was rejected by Fluminense. Besiktas, West Ham, and teams from the Gulf also made similar offers that were all rejected by the Brazilian club. Fluminense values the player at a minimum of €20,000,000. Martinelli's current contract is valid until 2027, and there is a desire from his club to extend it until 2030. According to Transfermarkt, his current market value is €14.00m. For the 2025/2026 season, Martinelli has made 3 appearances and provided 1 assist in the Campeonato Carioca, and has made 1 appearance in Série A.