Manchester United replaced Aaron Wan-Bissaka with Noussair Mazraoui in the summer.

West Ham paid £15million to sign Wan-Bissaka and his exit allowed United to bring in Mazraoui from Bayern Munich for €15m (£12.8m), with a possible €5m (£4.2m) in add-ons.

United have struggled to find value in the transfer market in the last 10 years but Mazraoui was an exceptional summer signing and his move was a rare example of a bargain transfer.

Sources discussed Mazraoui's versatility when he arrived in Manchester. He is a technically outstanding player and chalk and cheese to Wan-Bissaka. The Moroccan international has been an upgrade and it feels like he's played in every position apart from in goal for United this season.

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Sources said Mazraoui was signed because he is comfortable playing on either side of the defence and he's more than lived up to that billing by showing remarkable versatility.

Mazraoui has played four different positions in just his first few months at Old Trafford and has become an instant favourite among fans because of his consistent performances.

Regardless of where Mazraoui plays, he performs to the same standard and must be a dream to have in the dressing room. He started in the back-three against Viktoria Plzen on Thursday night and was one of the standout players, albeit not many emerged with credit on the night.

There is something incredibly endearing about a player who deliver 7/10 performances each week. They are the type of players every manager wants in their squad because they are reliable.

Mazraoui has hardly put a foot wrong since joining United and is one of the first names on the team sheet, although he might be asked to play in another new position this weekend.

The 27-year-old has played at left-back on a few occasions but hasn't started at left wing-back since Amorim was appointed and it makes sense to play Mazraoui there in the Manchester derby when the threat of the opposition and circumstances leading into the fixture are considered.

While Amorim might be tempted to stick with the same back-three of Mazraoui, Lisandro Martinez and Matthijs de Ligt, which was the choice on Thursday night, they look like an aerial vulnerable backline on paper and defending set-pieces has been a problem for United in last few weeks.

Leny Yoro, De Ligt and Martinez was the selection against Nottingham Forest but a goal was conceded from a corner and Harry Maguire was introduced to deal with the threat.

United's defensive presence improves when Maguire is on the pitch. Maguire has the desire and aggression that is needed to win aerial duels, and the former club captain seems like the logical choice to deal with Erling Haaland, which means the backline would need to be tweaked.

"We put Harry Maguire on because of set-pieces," explained Amorim after Forest. "To control more who was winning all the first balls, the only way to attack Nottingham was transitions, to try and win first and second balls. When Harry was on the pitch he won all the first ball."

United are suddenly being targeted from set-pieces and City have dead-ball specialists who can cause chaos with deliveries into the box, which strengths the case for Maguire to start.

If Maguire, De Ligt and Martinez start, which seems like the best option, Mazraoui shouldn't be moved to bench and should start at left wing-back, with Amad on the opposite side.

Amad started in an advanced role against Viktoria Plzen and played the full match, which must cast some doubt over his involvement on Sunday, but it would be bonkers not to start him.

Most fans would probably agree the best back five for the Manchester derby would be: Amad, Maguire, De Ligt, Martinez and Mazraoui. It might be a slight risk playing Mazraoui in a new role in such a big game but there's enough evidence to suggest it shouldn't be a problem.