Diego Besio, a 19-year-old Swiss-Spanish centre-forward, has signed a contract with St. Gallen valid until 2030. Roger Stilz, the FCSG-Sportchef, praised Diego Besio's qualities and his performance in past matches. The Switzerland U20 international has earned 2 caps. According to Transfermarkt, his current market value is €500k. In the 2025/2026 Super League season, Besio has made 14 appearances, scoring 2 goals and providing 2 assists.