is expected to enter the dugout as early as next week once a compensation agreement is reached with Sporting. The era is over after two and a half years, and that could soon mean the end of an era for several of his players.
Amorim will arrive at with desperately needed fresh ideas, his 3-4-3 formation and, naturally, his own signings to fit that system in time.
Express Sport looks at four current United players who could be under threat of being pushed aside once the Portuguese tactician's reign begins.
Tyrell MalaciaTyrell Malacia's future at the club would be in serious doubt even if Ten Hag were at the helm for a fourth summer.
After multiple knee surgeries, the 25-year-old left-back has been sidelined for over 15 months.
Hope of an impactful return has diminished by the month, and the left-winger back in Amorim's system requires a high level of physicality and fitness.
For that reason, Luke Shaw could also easily feature on this list. It wouldn't be surprising if one of Amorim's first signings fills the position.
CasemiroCasemiro is nearing the end of his United stay, which is simply factual, despite his performance levels this season being raised.
The 32-year-old was expected to leave in the summer and will undoubtedly be linked with an exit next year, too.
A younger Casemiro would be the perfect fit for the ball-winning defensive player in Amorim's midfield pairing.
However, the Sporting boss will likely be chomping at the bit to reunite with his former player, Manuel Ugarte, who represents Kobbie Mainoo's long-term partner.
AntonyIt's becoming increasingly apparent that Antony has no future at Old Trafford. Would it be too harsh to say that's been evident since he first kicked a ball for the club?
His performances have been nowhere near that of a £30million player - the maximum fee Ole Gunnar Solskjaer wanted United to pay Ajax for him during his reign.
But £86m? It's a travesty and one of the most prominent black marks on Ten Hag's tenure. Even the Dutchman clearly lost faith in Antony, handing him just one start this season.
With one of Amorim's two 'wingers' being an attacking midfielder, minutes will become even more challenging to come by.
Marcus RashfordNow, hear me out... Marcus Rashford could well thrive under Amorim. Ten Hag temporarily helped the United No. 10 reignite his unstoppable flame, and history could repeat itself under a new coach.
But as mentioned above, competition is about to become even more fierce in the attacking positions, and Amorim will inherit one of the world's most exciting young wingers, Alejandro Garnacho.
Now 26, Rashford could finally pursue a long-linked fresh challenge at the end of the season. He's been the poster boy of more rebuilds at Old Trafford than anyone would've liked.
United have a new wave of forwards in Garnacho, Amad, Rasmus Hojlund and Joshua Zirkzee. If sparks don't fly with Amorim, Rashford could become a thing of the past.
You may also like
1 killed, many hurt in Andhra Pradesh 'onion bomb' explosion
Gossip Girl's Ed Westwick announces he's to become a dad two months after wedding
Ruben Amorim's three crucial traits that Man Utd hierarchy admire most about new boss
Two militant groups active in J-K's Doda district: SSP Mohd Aslam
Helmut Marko slams Red Bull ace for 'ruining' rival's lap as duo's noses put out of joint