The squad has started training under Mourinho's guidance, and he has told the club's players involved in Spain's World Cup success that they must report back a week ahead of their previous schedule on August 2.
However, Casillas insists there are no problems between the likes of himself, Sergio Ramos, Xabi Alonso, Raul Albiol, Alvaro Arbeloa and their new club coach.
When asked about the early return, Casillas said: "That's fine. I have spoken to him a couple of times and I like his way of thinking."
"He wants the players to come back rested and ready to work. Being world champions makes you forget about everything," The Independent quoted Casillas, as saying.
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