This is a problem that Manchester United have never really faced. But now, coach Ruben Amorim is forced to find a solution in the absence of Bruno Fernandes.
Fernandes is not only the captain, but also the "soul" of Man United's playing style and is almost always present in the starting lineup. After arriving at Old Trafford from Sporting Lisbon in January 2020, the creative midfielder has hardly missed a single game.
The Portuguese international has only missed two games in the 2023-24 season due to a knee injury, before missing another game due to illness. Apart from those rare times, Fernandes has always been a near-default name in the starting lineup: 308 appearances, contributing 103 goals and 93 assists.

It is undeniable that Fernandes is Man United's best and most stable player. He could even be seen as the most important factor for any Premier League side, given Amorim's coverage and absolute influence in the system. And then, right when the "Red Devils" needed the most support, Fernandes could not play.
"We still can't decide how long Fernandes will be out," Amorim said after the loss to Aston Villa. Meanwhile, Diogo Dalot described this absence - at least in the match against Newcastle on Boxing Day - as "very big".
In addition, Bryan Mbeumo, Amad Diallo and Noussair Mazraoui are participating in the African Football Cup, while Harry Maguire and Matthijs de Ligt are also unable to participate due to injury.
The word "giant" is probably not enough to describe the personnel problem Amorim is facing. The January transfer window is approaching, but the Portuguese coach has given a clear signal - not buying in a panic just to lose space in the squad.
"I'll see what we do. I think Kobbie Mainoo and Bruno Fernandes are both absent, so we will consider it. We will find a solution. There is no excuse. We need to win the next match and we will try to win.
What we cannot do is until January and then try to do everything hastily, make mistakes and then repeat many other mistakes.
I will not sit down with Director of Football Jason Wilcox and CEO Omar Berrada and say we need a lot of players. Because we have a plan. If we have to suffer, the interests of the club are paramount," Amorim added.

So what is that plan? At least Amorim has another boost thanks to Casemiro's return from suspension. The Brazilian midfielder was absent from the 1-2 loss to Aston Villa after picking up his fifth yellow card of the season. With his experience and class, Casemiro is almost certain to be a "ininger" in midfield, but the big question remains: who will be the one to pair him?
Mainoo's injury came at the worst possible time. The 20-year-old player had to accept being on the bench for most of the season in a state of confusion, and right when the opportunity opened up, he could not play. Amorim insists he sees Mainoo as an attacking midfielder, but everything is now just a hypothetical point.
Looking at the first-team list on Man United's homepage, the level of the military crisis is very clear. Fernandes and Mainoo are both injured, while Toby Collyer and Dan Gore are on loan. That means in midfield, Amorim has only three fit names left: Casemiro, Manuel Ugarte and Mason Mount.
Amorim's problem is not only to patch the formation in the short term, but also to find a structure that is balanced enough for Man United to continue to stand firm when missing the most important link in the midfield.