Man United visit the Etihad Stadium after September's international break as Amorim and co seek back-to-back Premier League victories.
The Red Devils were last-gasp winners over Burnley during the final game before this month's break for international fixtures, defeating the Clarets 3-2 courtesy of Bruno Fernandes' stoppage time penalty.
Man United have struggled throughout much of 2025, though, and it was hoped a full pre-season under head coach Amorim and the arrival of a new attacking trio would galvanise the club.
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While the result against Burnley indicates the team are moving in the right direction, they will face their biggest test yet away against Pep Guardiola's Man City in less than a fortnight.
In the lead up to that match, Portuguese international Diogo Dalot has withdrawn from the national team squad citing 'muscular discomfort'.
Dalot has appeared in each of the team's three Premier League fixtures so far this term, starting in their season opener against Arsenal, coming off the bench in the 1-1 draw with Fulham and completing the full 90 minutes versus Scott Parker's Clarets last weekend.
The 26-year-old also featured throughout Man United's Carabao Cup exit to Grimsby Town just over a week ago.
Whether Dalot's departure from the Portugal camp is precautionary or something more serious remains to be seen, but it is hardly ideal for compatriot Amorim.
The head coach is under pressure to turn the club's fortunes around after £200 million worth of attacking players was added to his squad over the summer transfer window.
If Dalot is absent for the visit to Man United's city rivals, Amad Diallo is likely to deputise as the right-sided wing-back.
The Ivorian winger is naturally more attacking than Dalot, therefore would be put to the test against Man City's wide attackers.
