The 53-year-old has put pen to paper on a deal with the Red Devils to succeed Louis van Gaal as United’s permanent manager following months of speculation.
Mourinho’s appointment as United manager is his first job since the Portuguese coach was sacked in December following Chelsea’s dismal start to the Premier League campaign.
The new United manager won three Premier League titles, FA Cup and three League Cups during two spells in charge of the west London club.
Former Chelsea midfielder Nevin explained what Mourinho will bring to the Red Devils following his appointment as United manager.
“From the very start of his career in coaching Jose Mourinho has had this incredible self-belief, great knowledge and incredible attention to detail, but also this ability to think outside the box in a way some managers don’t,” Nevin told BBC Sport.
“He’s very willing to change things and adapt things in more complex ways when he has to and when it has to be simple, he will be simple.
“I have talked to him a few times about tactics. This guy is on a different level completely. In one game he made a number of changes within a three-minute period that other managers would take three games to do.
“He made radical changes, extreme changes that would not have even entered the mind of most managers. He not only did it, he did it with speed and they worked.”
The 20-time English champions ended a three-year trophy drought last weekend after United eased to a 2-1 extra-time victory over Crystal Palace in the FA Cup final at Wembley.
United have won the Premier League title since 2013.
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