The former Chelsea boss signed a three-year deal with the Red Devils after days of talks and plenty of speculation surrounding his future.
Mourinho has been out of work since being sacked by Chelsea back in December following their disastrous start to the season.
And United have been on the lookout for a new manager since they opted to sack Louis van Gaal on Monday following the club’s fifth placed finish in the Premier League.
Mourinho will now turn his attentions to the job at hand at Old Trafford as he prepares for an immediate return to the Premier League.
And celebrity Arsenal fan Morgan admits that he wishes the self-proclaimed Special One would move to Emirates Stadium.
Morgan tweeted on Friday morning:
Mourinho will be brilliant at United. Anyone who thinks otherwise is a footballing neanderthal.
Just wish he'd come to Arsenal.
— Piers Morgan (@piersmorgan) May 27, 2016
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