Jose Mourinho has opened the door to some of the most intriguing moments of his extraordinary managerial career in a new documentary.

Across three episodes, the Portuguese coach reflects on his time at some of Europe's biggest clubs, revealing details about dressing-room disputes, transfer decisions and his relationships with some of football's biggest figures.

Here are five of the biggest revelations from the documentary.

Mourinho believed Real Madrid were “spoilt”

Mourinho revealed that his relationship with Iker Casillas quickly became difficult after arriving at Real Madrid.

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The former goalkeeper recalled their relationship as extremely cold, while Sami Khedira described the resulting dressing-room atmosphere as a nightmare.

Mourinho, however, stood by his approach. He said Casillas initially approached him about extending national-team holidays, changing training times and avoiding team hotels.

“In a short period of time, I realised they're spoilt,” Mourinho said.

He nearly became Sir Alex Ferguson's successor

Mourinho revealed that he had actually agreed to take over from Sir Alex Ferguson at Manchester United in 2013.

Ferguson confirmed that Mourinho later called him in tears, saying he had promised Chelsea he would return and could not break his word.

Chelsea had Bolton training footage

Mourinho's Chelsea staff used extensive video analysis, but John Terry was stunned when footage from a Bolton training session appeared during a team meeting. “I am actually still not sure where he got the footage from!” Terry said.

Mourinho takes a dig at Pep Guardiola

Taking an apparent swipe at Pep Guardiola, Mourinho said he views sabbaticals as a sign of weakness. “For me, sabbatical means weakness,” he said, insisting that he never needs a break from football.

Beating Chelsea with Inter felt like revenge

Mourinho admitted that eliminating Chelsea in the 2009-10 Champions League with Inter carried extra meaning because Roman Abramovich had previously sacked him.

“I was playing against Roman that game. I was playing against a guy that sacked me,” Mourinho said.

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