It is a friendship that has spanned 15 years, survived countless controversies and sparked a thousand debates but that one could argue, has allowed Spain to make history by securing a third consecutive major international trophy with Euro 2012.

Notoriously humble and driven to succeed, the similarities between Iker Casillas and Xavi Hernandez were apparent from an early age, when the duo first met in the Under-17 FIFA World Championship in Egypt in 1997. Neither was outspoken, both were understated but their talent was evident as they led their country to a third place finish.

It was to be a friendship of firsts. Together the pair enjoyed their first success on international level two years later in the 1999 FIFA World Youth Championship in Nigeria when Spain lifted the trophy and less than a year later, they played as opponents in their respective first clasico in the Santiago Bernabeu on February 26, 2000.

The closeness of Xavi and Iker struck me from day one,” said Antonio Fernandez Marchan, who worked alongside sporting director Fernando Hierro with the Spanish Football Federation from 2008 to 2010 and saw first hand the duo’s affect as Spain transformed from European Champions to World Champions.

Growing into symbols of both club and country, Xavi and Casillas helped their respective teams to unprecedented success. However, for all their shared history and respect for one another, the strong rivalry between Barcelona and Real Madrid threatened to jeopardise both their enduring friendship and the harmony within the Spanish national team.

“They threw themselves to the ground, as usual,” said a disgusted Casillas after the Supercopa match between the two clubs in August 2011.

“The image of Real Madrid is pathetic,” cried Xavi after a now infamous match between the two sides that saw Jose Mourinho poke Tito Vilanova in the eye.

Tensions between the two players had started some months ago when their clubs faced each other in the Champions League semi-finals. Xavi was reportedly furious at Casillas for his reactions after Gonzalo Higuain’s goal was disallowed and annoyed at his attempts to get Pedro Rodriguez booked. Spain was now very worried about the implications these clasicos would have on the national team.

For the sake of Spain and for his own personal credibility, Casillas took the decision to call both Carles Puyol and Xavi after the match to apologise for his own comments and ask for an explanation with regards to the remarks made by the midfielder in the mixed zone after the match.

According to Madrid based newspapers, Xavi ‘did not bother to pick up’ whilst Mundo Deportivo noted that Casillas simply dialled a number no longer in use. Upon being told of the goalkeeper’s attempts to call him by TV3, Xavi contacted the Real Madrid captain to resolve the matter. Three weeks later, Casillas posted a picture of him and Xavi alongside Pepe Reina and Fernando Llorente on Facebook. This was his way of assuring the public. They were all still friends.

Mourinho felt betrayed and Xavi’s father recently confirmed the Coach’s anguish: “Iker got into a lot of trouble with Mourinho over his friendship with Xavi. These problems became public last season and everybody knows about it.”

Tensions between both captain and Coach continued to grow and moles within the dressing room described Casillas as ‘indifferent’.

Florentino Perez was allegedly forced to intervene and phoned the Spanish captain pleading with him to pledge allegiance to the Coach and indulge in Mourinho’s quest for dominance. As a Madridista, Casillas had no other option but to agree in order provide a stable club environment. Thus began the talk of dubious referee decisions when it came to Barcelona.

“Xavi and Iker never had any intention of ending their friendship,” continued Xavi’s father. Indeed they did not and Casillas continued to use Facebook to his advantage. Posting pictures of him with Barcelona players in October 2011 before putting up one of him and Xavi as youngsters during Euro 2012, the duo continue to reaffirm their friendship and together alongside the sensational work of Del Bosque, led their team to a record breaking triumph.

La Liga - Club News