Antonio Conte's league leaders arrive at Old Trafford on Sunday for what promises to be a fascinating clash, putting the most successful manager in Chelsea's history in the spotlight once more.
Mourinho, sacked by the London club in December 2015, was humiliated on his first return to Stamford Bridge in October and took umbrage with Conte's touchline histrionics as the Blues romped to a 4-0 win.
The west Londoners' fan base was the subject of the Portuguese's ire when the sides met in the FA Cup last month, having been goaded by a section of supporters and called 'Judas'.
Mourinho returned fire after the 1-0 loss by pointing out that "Judas is number one" in Chelsea's record books, although he insists Sunday's encounter is like any other match.
"You say that word 'emotion'," the United boss said when asked how his emotions differ after two high-octane meetings in the capital.
"For me, it is just a game. One more game. No difference for me."
Asked if there was nothing special about the game, Mourinho: "No, not at all."
Whatever Mourinho says publicly, victory would surely be sweet against a side that have gone from faltering under his tutelage to become runaway leaders.
United, meanwhile, have gone on a 21-match unbeaten Premier League run since October's Stamford Bridge humbling, but a failure to take three points from games they have dominated leaves them fifth.
That lack of cutting edge reared its head again on Thursday as Anderlecht snatched a late 1-1 draw in the first leg of their Europa League quarter-final.