A major sticking point during Ruben Amorim's rocky managerial tenure at Manchester United was his loyalty to a clearly broken tactical system that did not provide the desired results.
Now that Amorim has been sacked, a new coach can come in and make sweeping change to the tactical approach moving forward.
However, there will be a transition period — likely a lengthy one, given the club may wait to hire a new permanent boss in the summer when options will become more open.
For the time being, caretaker manager Darren Fletcher, and whoever is ultimately hired as interim boss through the remainder of the season, will have to decide how to set up the team.
Here are some options for Fletcher as he looks to get United back track, starting with their Premier League visit to Burnley.
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What is Man United's best formation? Four tactical options for Darren Fletcher
Caretaker manager Fletcher has a few options at his disposal for how to set up United in the wake of Amorim's departure.
3-4-2-1: Keep change to a minimum
Lammens
Yoro, Heaven, L. Martinez
Dalot, Casemiro, Ugarte, Shaw
Dorgu, Cunha
Sesko
The simplest option available to Fletcher is also maybe the most complicated. Sticking with Amorim's 3-4-2-1 setup he used for most of his time in charge would require the least amount of change to the tactical approach given the short period of time to prepare.
However, this option would also be the most questionable given the stark lack of results that Amorim's tactics brought United. Would sticking with his methods even after his departure really be the best way forward?
MORE: Ruben Amorim's final record at Man United
4-3-3: Wilcox's preference
Lammens
Dalot, Yoro, L. Martinez, Shaw
Mount, Casemiro, Ugarte
Dorgu, Cunha, Sesko
The most likely formation under Fletcher right now is a 4-3-3, the system reportedly favoured by director of football Jason Wilcox, but there are significant problems with this given the absences for the club.
There's no guarantee that Mason Mount, Bruno Fernandes or Kobbie Mainoo will be fit, although Fletcher hopes the former two can at least be in the squad, and so there would need to be some serious shuffling if none of them can find a way onto the pitch. If needed, Lisandro Martinez can step up into midfield, and in an even bigger pinch Matheus Cunha may be able to step back. Still, there might be better options for Fletcher that would fit the available players on hand.
4-2-3-1: Amorim's Plan B
Lammens
Dalot, Yoro, L. Martinez, Shaw
Casemiro, Ugarte
Dorgu, Mount, Cunha
Sesko
A switch to a more modern 4-2-3-1 formation would suit this squad well. It would allow Casemiro and Manuel Ugarte to play in a double pivot with more defensive responsibilities and fewer link-up requirements, while allowing Fernandes (when healthy) to play a true No. 10 role.
This would allow the likes of Amad Diallo (when back from AFCON duty) and surprisingly effective attacking option Patrick Dorgu to hug the touchline where they are at their best.
Amorim deployed this set-up for the win over Newcastle United on December 26, largely due to the number of first-team players missing, and it yielded a 1-0 win.
4-4-2: An old Ferguson favourite
Lammens
Dalot, Yoro, L. Martinez, Shaw
Dorgu, Casmiro, Ugarte, Zirkzee
Sesko, Cunha
Amorim showed at least some willingness to adapt towards the end of his spell, utilising a 4-4-2 formation against Bournemouth in the wild 4-4 draw. Clearly, there were issues defensively as the squad had not prepared for this well, but it showed signs of effectiveness, especially in the attacking third.
Unfortunately, until a few players return to full fitness and others are back from international competition, there is a distinct lack of wide options in the squad, especially on the left, to make this work. It might not be a good choice for Fletcher right out of the gate, even if it's a system he played in during his early years as a player under Sir Alex Ferguson.