The former Chelsea and Man Utd boss has a reputation for a hard-nosed, serial winner who often appears to lack empathy with those not on his wavelength.
His demeanour has led to problems at clubs in the past, but fans have been given a glimpse of what Mourinho is really like behind the scenes in new Amazon documentary All Or Nothing.
During the fly-on-the-wall series, Mourinho shows a side to him not usually seen under the glare of the matchday cameras, and Kane admits it was something he did not expect.
“Probably from the outside, before I knew Jose, you got that impression he was kind of stern and all about winning,” said Kane.
“But he’s actually really good off the pitch, getting to know you as a person, getting to know your family, texting you to make sure you’re alright.”
One scene during the documentary is from the first day of Mourinho’s managerial tenure at Tottenham.
The Spurs coach took charge just hours after Mauricio Pochettino had been sacked, and made a point of summoning Kane for a meeting early on.
Mourinho approached the striker in training to ask him to come to his office for a meeting the next morning, as he insisted Kane should go straight home after practice so he could spend time with his family.
What is your opinion of Mourinho after watching All Or Nothing? Have your say below.
Kane continued: “Everyone knows tactically he’s a great manager. Over the years he’s won many, many trophies – always finding ways to win in big games.
“But in any management you need to have that relationship with the players and be able to keep the players happy: whether you’re starting, on the bench, not in the squad.
“He’s got great experience of that as he’s managed some of the biggest players around the world.”
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