Joaquin Hernandez, Xavi's father, says the friendship between his son and Real skipper Iker Casillas was key to Spain winning the Euros.
Real coach Jose Mourinho was unhappy with his players mixing with their Barca counterparts, which upset both Casillas and Xavi.
"Iker had many problems with the demands of Mourinho, problems came to light and we all know, because Xavi and Iker never wanted to break their friendship," revealed Joaquin.
"At times it was very complicated because of the El Clasicos. Players who were partners and friends were about to lose this friendship. There were rifts. We saw the issue of Arbeloa, Xabi Alonso, Sergio Ramos, and the way they acted to their team-mates. The behavior of some players was not appropriate.
"Luckily Iker and Xavi got involved."