Real Madrid are calm over Barcelona's interest in Isco.
Barcelona have begun to express interest in gaining the services of the 24-year old midfielder.
But Real Madrid won't allow him to leave for their eternal rivals.
El Mundo Deportivo says an “Anti-Barça" clause is included in Isco's contract which would prevent the transfer.
According to the paper, it is a stipulation written into all of deals that Real Madrid have with their players.