The appointment of Ralf Rangnick as interim manager until the end of the season was confirmed on Tuesday (AEDT), a day after caretaker Michael Carrick managed a creditable 1-1 draw at Premier League leader Chelsea.
While he hasn't been a coach for the best part of three years, Rangnick's legacy in the Bundesliga and his influence on some of Germany's finest minds makes him a shrewd appointment for United, not least because he will take up a two-year consultancy role after 2021-2022.
This, then, is a decision taken by United with a view to long-term changes to their fortunes, not simply a quick fix to arrest poor results. Still, with more than half the season still to go, Rangnick could yet guide the Red Devils to some tangible on-pitch success over the coming months – provided that he gets to work quickly on some of their biggest problems.
There are five things Rangnick must address as soon as possible...
Fix the defence
United conceded 21 goals in the first 12 games of the season; they have never previously let in more at the same stage in the competition's history. In November alone, they have faced 60 shots, the most of any side in the division.
That tells you something about the state of their defence.
Of course, Rangnick's gegenpressing system is likely to demand off-the-ball contributions from every player on the pitch (more on that shortly) but the rearguard is in need of some serious fine-tuning. In particular, captain Harry Maguire and Luke Shaw have seen their individual form fall off a cliff since they helped England to the final of Euro 2020; it was telling that a good defensive performance against Chelsea on Monday came with both players sidelined.
Getting the best out of Shaw and Maguire, arresting Aaron Wan-Bissaka's decline and getting Raphael Varane fit and integrated into the side will be essential to Rangnick's aims.
Get Bruno firing again
So often United's star performer under Solskjaer, Bruno Fernandes is another who has endured a comparatively poor season.
He tallied his 50 direct goal involvement on his 58th appearance in October (30 goals, 20 assists), which is a tally only Andy Cole (43), Alan Shearer (54) and Eric Cantona (54) reached in fewer games, so it's not all bad. But the Portugal playmaker has scored just once in 19 appearances for club and country.
He looks a player in need of a lift and, so central is he to United's attack play, he could be Rangnick's first port of call at Carrington. Well, apart from...
Like a black hole devouring a gas cloud, all the noise surrounding United's performances seems to be drawn inexorably back to Cristiano Ronaldo.
It's a beguiling narrative: a five-time Ballon d'Or winner who has to start every game but who should not expect to start every game; a 36-year-old forward who no longer contributes enough to make up for any shortcomings, but one with six goals in five Champions League matches this season, two of them winners and one a last-gasp equaliser.
There are some writing off Ronaldo's chances of winning over a coach like Rangnick who demands hard graft from every member of his team, while others say the onus is on the incoming manager to construct a unit that brings the best out of the leading male international goalscorer in history. Time will tell what the future holds.
And just a note for the 'Ronaldo doesn't press' crowd: he made three more sprints and 21 more intensive runs against Chelsea than Jesse Lingard, who came on at the same time.
Tie down Pogba and tidy the squad
Some of Solskjaer's best work at United was putting together a strong squad, but that seemed to unravel in his final few months in charge.
Lingard returned rejuvenated from West Ham but, rather than cash in when there was a demand, Solskjaer kept the England international yet gave him just 63 minutes of league action. It's now likely he'll leave for nothing next June.
There were similarly strange decisions behind contract extensions for Eric Bailly and the seldom-seen Juan Mata, while Phil Jones is still at the club after two years of injury hell and Anthony Martial was retained despite falling way down the attacking pecking order. Goalkeeper Dean Henderson also appears unlikely now to dislodge David de Gea.
Then there is Paul Pogba, still yet to sign a new deal or announce plans to leave for free next year, whose agent wastes few opportunities to discuss potentially interested parties. The word is that Pogba is excited to work with Rangnick, but the France star is just one of several members of the United squad who needs clarity on their positions.
Give Donny a chance
It felt almost pre-ordained when Donny van de Beek scored the final goal of the Solskjaer era against Watford, having come on as a substitute to rapturous (and ironic) cheers from the visiting fans.
Van de Beek has spent most of his time at United being assured his chances would come, then left wondering when that would be. Having only started four league games in 14 months, the Netherlands international – who has lost his place in the national squad – would almost certainly have pushed to leave in January had Solskjaer stayed in the job.
Now, Van de Beek has the opportunity to prove himself to a new manager. Rangnick's methods might not be Cruyffian exactly, but they are certainly more closely aligned to the Ajax way than Solskjaer's focus on individual inspiration.