I heard their president is a nutjob. He'd rather lose Llorente for free next season than selling him for a price below the release clause.
They have got a lot of very talented players coming through at the moment and he will want to send a message to them that it's not easy to leave and send a message to clubs that it is hard to sign the players.
It's entirely possible that could prove to be worth more to the club over ten years than the 20m or so Juve are willing to offer for Llorente.
