Chelsea play the first-leg in Istanbul.
"We know Didier well," said the Chelsea manager. "For him, it is 'no friends' during the game. If for Didier it's 'no friends', for us it's 'no friends'.
"Before the game we will all be friends and there will be respect for a legend of this club - the same after the game. But during the match we have a job to do. He has his nature. And he has his job to do."
Mourinho has had to endure what he regards as an unnatural suspension of the strong friendship between manager and player before.
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