All of Jonny Evans (knock), Victor Lindelof (groin), Harry Maguire (calf) and Leny Yoro (foot) missed the 3-2 Europa League win over Bodo/Glimt on Thursday, and the tight turnaround makes it difficult to envisage any of them recovering in time for the weekend.
Yoro is on the verge of making his belated Man United debut after his pre-season injury, but Amorim is giving him ample time to hit peak fitness again, so he will not be rushed into Red Devils action.
As a result, the Man United boss could stick with the same defensive formula from Thursday evening, as Noussair Mazraoui, Matthijs de Ligt and Lisandro Martinez form the three-man guard in front of Andre Onana.
However, two alterations could occur in the wing-back areas, as Diogo Dalot should bump Antony down to the bench, while Tyrell Malacia - a surprise starter on Thursday - could make way for another injury-plagued defender in Luke Shaw.
Shaw and Dalot could comprise part of a brand-new quintet in the middle, as Kobbie Mainoo is surely in line for his first minutes under Amorim, likely alongside Casemiro in the centre.
Bruno Fernandes and Alejandro Garnacho have already made themselves indispensable in attack, leaving Marcus Rashford and Rasmus Hojlund to scrap for the final place; the latter's brace in midweek could just tip the scales in his favour.
Manchester United possible starting lineup:
Onana; Mazraoui, De Ligt, Martinez; Dalot, Mainoo, Casemiro, Shaw; Fernandes, Hojlund, Garnacho