FC Villarreal is among several clubs interested in Sergio Martínez from Racing Santander. FC Barcelona is also interested in the 18-year-old midfielder, and has a plan to loan the Spanish U19 international with an option to buy for their second team. TSG Hoffenheim and two other Bundesliga clubs have also been previously linked with Martínez, who is under contract at Santander until 2029 and has a release clause of three million euros.