The Sunderland manager and former Red Devils boss takes on his old side in a pivotal showdown today (1.30pm).
United travel to The Stadium of Light and cannot afford another slip up in their pursuit of a top-four finish.
Winning the Europa League is looking Mourinho’s most realistic route of qualification for the Champions League, but Premier League progress is still on the agenda.
Moyes and Sunderland are also desperate for the points with relegation looming large for the bottom club.
Jose Mourinho's Manchester United saw off David Moyes' Sunderland 3-1 on Boxing Day
You have to win trophies there and Jose has a trophy under his belt quickly
But reflecting on his brief time in charge at Old Trafford where he was sacked after less than a season in the hotseat, Moyes has given Mourinho some advice.
The Scot feels Manchester United have to get back in Europe’s elite club competition next term, which will help Mourinho bank some time to build his team.
“It will be very tight for them this season but I think United have to be in the Champions League,” Moyes said.
“You have to win trophies there and Jose has a trophy under his belt quickly.
Could this be Jose Mourinho's Manchester United side next season?
Fri, March 31, 2017
Could this be Jose Mourinho's Manchester United side next season if he secures all his summer signings?
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How could Jose Mourinho's side look next season?
“Every manager needs a bit of time and whoever is at Manchester United needs time to understand the club, its size and how it works. You can't turn it around quickly because it is a big beast.
“You don't get offered the Manchester United job if you're a bad manager. You only get that position if you've had something to show previously.”
Jose Mourinho is eyeing some top-class recruits for the summer, but Champions League football will certainly help lure the world’s best towards Old Trafford.
If United can beat Sunderland this afternoon, they will close the gap to fourth-placed neighbours Manchester City to four points, with Pep Guardiola’s side having played a game more.