Olympiacos is pursuing Oso, a 23-year-old Spanish-Argentinian left-back from Sevilla. He joined the club in January 2026, and in the 2025/2026 LaLiga season, he made 21 appearances, scored 2 goals, and provided 3 assists. His contract runs until 2027, and his current market value is €10.00m, according to Transfermarkt. Other clubs, including Nottingham Forest, Newcastle United, and Fiorentina, have also been linked with him. According to reports in May 2026, a potential transfer was valued at an estimated €5 million.