Machester United host Tottenham Hotspur on Saturday afternoon in what could be one of the most important matches in the Premier League this season.
Mourinho's United had been brushing everybody aside in the early months of the season until they faced Huddersfield Town last weekend.
The Terriers terrorised United and managed to hand Mourinho his first defeat of the season, which saw his team fall five points behind rivals Manchester City at the top.
The slip up also meant Mauricio Pochettino's Spurs side caught up with United and now the teams are level on points, with the Manchester club only ahead on goal difference.
If one team can win on Saturday, they will take second place for themselves and become City's closest challengers.
Ahead of the crunch fixture, fans would have expected mind games to be played, especially by Mourinho, who is usually the master of them.
But the build-up to Saturday's match has been pleasant from both men, and Mourinho has even praised his rival from north London.
“They are a very good team, one of the best in the league," he said on Friday, per the Evening Standard.
"They have a fantastic squad, a good manager, stability and years with the same manager, the same players. They are a really, really, really good team.”
The United boss was also asked another question relating to his left-back Luke Shaw, who has recently publically praised Pochettino in a new book about Spurs, written by Guillem Balague.
Shaw has expressed his intention to one day work with his former manager Pochettino, who was in charge of Southampton when the 22-year-old had the best year of his career.
Revealing that you'd want to one day work with an old manager while being out of favour at your current club probably isn't the best way to get back into the good books.
But Mourinho, perhaps surprisingly, responded positively to his defender's comments.
"I would be very disappointed if his words were different. For me, they are the perfect words," the Portuguese coach said, per Sky Sports.
"Football is full of examples of lack of character, Luke Shaw was just honest. The manager that helped him to come to the first team, the manager who brought him to the best point of his career.
"It's a manager that he doesn't forget, it's a manager that he likes a lot and it's a manager that maybe one day he would like to be reunited [with] again."
Mourinho's reaction is quite a change from normal.
His measured response suggests that Shaw is still very much in his future plans, so we could see the English defender back in United's starting 11 again soon.