With his side heading for a victory in the final minutes of the game at the Riverside, Mourinho watched the right back chase down a back pass only for Victor Valdes to slip and allow him to tap in.
It was the ideal end for United, who had allowed the home side back into the game after leading 2-0 through Marouane Fellaini and Jesse Lingard goals.
And Mourinho’s reaction to the goal is pretty funny:
? | Jose Mourinho's reaction to Antonio Valencia's goal against Middlesbrough. pic.twitter.com/mOnEIOCnz4
— Man Utd Stuff (@ManUtdStuff) March 19, 2017
Like the rest of us, he obviously knew that the Valencia goal put the seal on the win just as Boro were trying to push for a late equaliser.
With the victory, United move three points behind fourth-placed Liverpool with a game in hand.
And they’ll be watching on at the other side of Manchester as rivals City take on Liverpool in today’s later game.
If City can manage to get a result, it will keep Liverpool within touching distance of United and their aim of playing Champions League football next season is still a realistic one.