Zinedine Zidane is thought to be a keen admirer of Isco but equally would not block a transfer should a big-money offer come in from elsewhere.
Juventus, Milan and Manchester City have been among the clubs linked to the playmaker but no interest has ever been formalised with an offer.
The 26-year-old had been frozen out of the starting XI by previous Madrid boss Santiago Solari – not starting a match across La Liga or the Champions League under the Frenchman’s predecessor.
Isco has a contract at the Santiago Bernabeu until 2021 but found the net just three times in a mere 11 La Liga starts last season, with his future appearing to be in the balance.