Real Madrid's former president Ramon Calderon says Jose Mourinho failed to cope with the pressure of being in charge of the Spanish giants.
The Chelsea boss joined the Los Merengues after winning all there was to win at Internazionale but came under heavy fire after losing 5-0 in his first "Clasico" against Barcelona.
At Real Madrid, the 52-year-old won La Liga in 2012 and the Re Copa in 2011.
He returned to Chelsea in the summer of 2013 and was given a warm reception by the fans on his first game at Stamford Bridge against Hull City.
"To be a manager of Real Madrid is really, really difficult," Calderon told BBC World Service.
"See what happened to Mourinho; he is someone who is used to coping with pressure and he couldn't.
"When Mourinho left, things were in a really bad situation.
"He had to leave the club after three years of a lot of problems, a lot of confrontations."
