The Red Devils made the trip to Turin fresh from a chastening 1-0 loss to the Serie A side a fortnight ago, after Paulo Dybala netted a first-half winner at Old Trafford.
Juventus dominated their first meeting of the group-stage campaign and the Italian champions were on top for large parts of the game at Juventus Stadium mid-week.
Cristiano Ronaldo broke the deadlock with a superb clinical finish but Dybala, Miralem Pjanic and Sami Khedira all squandered chances to extend their lead.
And Manchester United punished their opponents following the introduction of Marouane Fellaini and Juan Mata in the second half in Turin.
Mata equalised with a superb free-kick before Alex Sandro scored an own goal with the Juventus defender under pressure from Belgian midfielder Fellaini.
Ander Herrera, Paul Pogba and Nemanja Matic added muscle to Manchester United’s midfield, while Fellaini’s aerial ability caused panic in the penalty area.
Asked during his weekly Ask Keown column with the Daily Mail whether Mourinho has got his swagger back, the former Arsenal defender was quick to praise the Portuguese head coach’s tactics.
“I don’t think he has ever lost his swagger! What he proved in Turin was that he can still give his team the tactics to make them competitive against superior opponents.
“In recent weeks, United have been reactive. It has taken a disappointing first half to get them to produce a match-winning performance.
“This victory against Juventus was as a result of a carefully executed plan — something we have seen Jose Mourinho do many times in the past.
“The midfield was key to United’s improvement. When Juventus won at Old Trafford, Mourinho had Paul Pogba and Nemanja Matic sitting in midfield with Juan Mata off the front.
“They did not know when to press and United were simply not in the game long enough to hurt Juventus.
“Mourinho learned from that. With Ander Herrera sitting alongside Matic in Turin, there was far more industry in the midfield.
“They pressed Juventus at the right times. When they had a goal kick, United were right up against them and it was only the Italians’ good play that got them out.
“Juventus still had enough chances to win the game but they were not nearly as emphatic as they were at Old Trafford.
“United were far better at restricting them. Their tactics gave them the platform to make them competitive and win this match.”
Mourinho’s next challenge will be orchestrating a tactical setup that can cause Manchester City’s team problems in the derby clash at The Etihad on Sunday afternoon.
The Citizens are sitting nine points ahead of Manchester United at the top of the table and haven’t lost a game in the Premier League in the current campaign.
The Red Devils did ease to a 3-2 win in their most recent meeting at The Etihad after goals from Pogba and Chris Smalling turned the game on its head.
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