The Serbian midfielder signed for the Red Devils back in July after he was deemed to be surplus to requirements at Stamford Bridge by Antonio Conte.
The move came as a surprise to many, because Matic had just played a key role in helping Chelsea to win the Premier League title under Conte last season.
The 29-year-old midfielder has slotted seamlessly into the first team at Manchester United and has started all 10 of the Red Devils’ Premier League games this season.
Matic will be expecting to line up for Manchester United when the Red Devils return to Premier League action with a crunch clash against Chelsea at Stamford Bridge on Sunday.
And Mourinho has now lifted the lid on how Matic’s transfer to Old Trafford from Chelsea unfolded.
Speaking to Sky Sports News, Mourinho said: “I was surprised when [Matic’s] agent called me to say ‘do you want him?’.
“I was surprised, but he’s an agent I know well.
“Normally he’s very direct and objective, he doesn’t waste time, he doesn’t try to get people to be interested in his players to improve their situation at their club.
“Normally he’s very straightforward, so when he told me ‘you can have him if you want’, of course I want.”
Manchester United head into their clash with Chelsea in second place in the Premier League table and five points behind leaders Manchester City after 10 games.
Chelsea, meanwhile, are fourth and nine points behind Pep Guardiola’s pace-setters.
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