The home side, with Mata often at the heart of proceedings, enjoyed a buoyant first 20 minutes against Marco Silva’s men but went into the break with nothing to show for their endeavours.
Mourinho’s men finally broke the deadlock after 56 minutes following a close-range Mata strike before taking firm hold of the tie with a late Marouane Fellaini header.
When asked what Mourinho told his players at half-time, Mata said: “We needed to play quicker, we needed to put more tempo in the game.
“Basically that we needed to create a little bit more. I think we had a few chances in the first half to score earlier.
“We have done that in the second half: 2-0 is a good result but it’s still not done.”
It is a testament to Mourinho’s managerial assiduousness – and indeed to the relationship between the first team and their manager as a whole – that a notable reaction came after half-time.
United were notably quicker on the ball, passing with more purpose and precision as they went forward, and the opener came through nothing more than persistently putting bodies into the box.
Unearthing such a reaction from your side is far from simple, but Mourinho has clearly cultivated a genuine bond with his squad.