Mourinho opens the black box: the war with Barcelona and the dressing-room spy

Mourinho revealed that his first three conversations with Casillas left a clear impression on him. In the first, the Real Madrid captain asked for more time off for the players of the Spanish national team. In the second he requested that training be pushed back by an hour because of Madrid's traffic. The third revolved around the team not going to the hotel before matches, meeting directly at the stadium instead.

Mourinho said: "I realised in a short time that they were spoiled."

That phrase sums up the impression the Portuguese coach came away with about the Real Madrid dressing room. It also explains part of his philosophy when he took charge in 2010. He inherited a group packed with stars, and he believed his task was not to teach them how to play football, but to impose a methodology and discipline together.

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The documentary also revisited the famous feud between Mourinho and Casillas. It erupted after the Real Madrid goalkeeper called Barcelona captain Xavi Hernandez to try and ease the tension between the two camps, with the bad blood from El Clasico bleeding into the Spanish national team setup.

Casillas found himself caught in the middle. He captained both Real Madrid and Spain at the same time, and the clash of loyalties left him deeply uncomfortable. "You were facing your teammates who were your enemies on the football pitch, and then they become your teammates with the national team. I didn't like to see that and I told the coach so," he said.

Mourinho saw it completely differently. For him, keeping the rivalry white-hot was non-negotiable as long as the two clubs chased the same silverware.

"I told them: this is the Barcelona and Real Madrid clash. When you go to the national team you can kiss each other, but not now. This is war. There are things I don't accept and will never accept. And when someone doesn't respect me, it turns into a problem," he said.

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The documentary also revisited one of the period's most explosive incidents: information leaking from inside the dressing room to the media.

Mourinho wanted total control over anything relating to the team. Then one of his line-ups leaked, and the Portuguese coach reacted furiously.

Casillas recalled the scene inside the dressing room, saying: "He lost his temper. He came in and started hurling all kinds of insults at us, and told us everything. He said we were the ones responsible for what was happening."

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According to the former Real Madrid captain, Mourinho went even further, hitting a bottle and slamming his office door shut.

These incidents matter beyond nostalgia for a controversial era. Mourinho's words carry fresh weight now that he has returned to lead Real Madrid. Once again he faces a squad packed with big names, and once again he must manage the stars, the leadership hierarchy and the clashing personalities in the dressing room. The task looks strikingly similar to the one he handled during his first spell.

His previous experience made one thing clear. He still believes in imposing control and discipline, and in never loosening his grip on the team.

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