Courtois believes his motivating personality and astute managerial skills are the source of the success.
He told the Mail on Sunday: "Working for him [Jose Mourinho] now, it is easy to see why his sides have that fighting mentality. He motivates you.
"With Mourinho, everything is good. He knows when to be among his players, as 'one of us' making jokes as a friend, and when to be strong and distant, even severe. That's how it has to be to get the team sharp.
"[Diego] Simeone did that, also, in his own way. He was an ex-player so he knew how we ticked."
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