The Barcelona star has been unhappy to see his Spain team-mate suffer such a controversial season at the Bernabeu, while also discussing his determination to keep playing
The goalkeeper has been exiled from the first-team by Jose Mourinho and regularly criticised by the coach in public, with the Santiago Bernabeu boss preferring to select January signing Diego Lopez between the sticks.
Xavi has been dismayed to see his club rival and international colleague go through such a hard time and says it is not what a player of Casillas' standing deserves.
“I don't like to see an important player like Iker going through something like this,” he told a press conference.
“It is terrible and I don't like it at all. Not so long ago they were putting him forward for the Ballon d'Or and now he's being discarded.
“He's my friend, he is a role model for a lot of people, he is captain of Spain's national team - he doesn't deserve this. I don’t know if Mourinho will continue [at Real Madrid] or not.”
Xavi’s long-term fitness is often an issue debated when Barca’s squad is analysed but the iconic midfielder insists he is still as keen as ever to play regularly - both for club and country.
The 33-year-old added: “Physically, I am prepared to keep going - that's why I signed a three-year contract extension.
“I haven't left the national team and I want to be with Spain for the Confederations Cup and World Cup 2014. I want to keep performing to a high level and I see myself being able to do so.
“I enjoy playing every three days - that's how you can build up rhythm and form. I want to be with Spain for the Confederations Cup and I want to win it.
“There are a lot of games to get through but that's because of the way the calendar is. At the end of the season, your legs are tired.”
The Camp Nou club’s latest Liga title was Xavi’s seventh in a star-studded career that has also seen him win three Champions League medals.