Football clubs are in an almost permanent state of flux. The arrivals of new players and managers and the ebbs and flows in form and tactical approaches mean the relative importance of each player within the squad changes all the time.
With that in mind, we thought we would look back a year and see which players at Manchester United have moved up or down the pecking order of importance when compared to where they stood in November 2016.
We are selecting four on each side of the list, starting with the player who has fallen the furthest and working our way through second-, third- and fourth-placed fallers. The fourth-, third- and second-placed climbers follow, with the player whose relative importance has increased the most presented last.
Only players who were at the club last year and are still around are eligible. Technically, signings since November 2016 are all infinitely more important to United than they were this time last year given they had no previous benchmark.
It is important to stress this is not a measure of a player's quality, only his utility to the squad.
And it is with a heavy heart that we begin with a player close to many United fans' hearts.
Biggest Fall: Ander Herrera
At the end of last season, after a good deal of thought, Ander Herrera came second to Antonio Valencia at the top of B/R's United player rankings for the 2016/17 Premier League campaign. It was a close call, and when Herrera won the fans' vote for Player of the Year at the club's end-of-season awards, it was hard to argue.
Were we to construct rankings for this season, though, the popular Basque would not crack the top 15.
Herrera's importance was always likely to diminish once Nemanja Matic rolled into town. After all, Mourinho would not spend £40 million on a player he had worked with before to bring in a back-up.
There was a chance the plan was to play a 4-3-3 with Paul Pogba, Matic and Herrera, but that has hardly happened. Instead, the Spain international played second fiddle to Matic before Pogba's injury in September and then returned to the side out of form and seemingly unsure of his role in it.
It makes sense. Last season, he had it drilled into him that his job was to be the solid—positionally disciplined counterweight to Pogba's attacking intent. This season, he was in the side with Matic but did not seem to be able to recapture the more attacking instincts he previously displayed. Remember, this is a player who frequently played at No. 10 for Athletic Bilbao but whose touch and eye for a forward pass seem to have deserted him.
From being the team's most consistent performer to being a bit-part player who has too often fluffed his lines, sadly Herrera is an easy pick for first here. United fans will be hoping better lies ahead for a player who is still well-liked among fans.
2nd-Biggest Fall: Zlatan Ibrahimovic
This one is simple. Last season, Zlatan Ibrahimovic was United's dominant, line-leading centre-forward, the man tasked with finishing the chances his team-mates made for him. In the same way as Matic's arrival affected Herrera's place in the pecking order, Romelu Lukaku's signing changed Ibrahimovic's role.
Zlatan Ibrahimović @Ibra_official
Thanks to everybody that stod by my side for the last months.Thanks to my family,coach,teammates,Mino,DarioFort,Dahan,DrFu,DrVolker,Manutd and the most important my fanz.This was not a one man work without all of you I would not be playing fotball today Thank you and I ❤️ you https://t.co/XpTCWMaEIn
There was a point following a serious injury towards the end of last season when it was even unclear whether he would play for United again. Everyone knows the end of that story now, and he received a rapturous reception when he took the pitch against Newcastle United on Saturday evening at Old Trafford.
But he made a cameo in that game, and it seems likely that cameo appearances will be his stock-in-trade from now on. Lukaku has endured a bit of a dry spell recently—though that ended on Saturday—but the start of the season showed just how effective he can be as United's No. 9.
Ibrahimovic is still a remarkable physical specimen, but he is in the twilight of his career. The 36-year-old can still influence the direction of United's season. But last time out he was integral, and this season he will likely be a lot more peripheral.
3rd-Biggest Fall: Daley Blind
Daley Blind's importance to the squad has steadily diminished during Mourinho's time in charge. The Dutch utility man is now the second- or third-choice left-back and nowhere in the central-midfield discussion.
He will only get on the pitch if Ashley Young is needed somewhere other than left-back in a game in which Mourinho wants to attack or if he wants to give Young a rest. Matteo Darmian takes the spot ahead of him in games in which the manager is looking for stability, and Young has become the go-to attacking choice.
Luke Shaw is still at United, but he is more concept than footballer as far as United's starting XI in meaningful games goes.
If this were a comparison chart for those surviving from Louis van Gaal's reign, Blind may be even higher up the list. Under his compatriot, he became a starting centre-back. As hard as it is to imagine, he began last season under Mourinho starting games at centre-back in a back four. That would seem near impossible now in all but the worst injury crisis. He could maybe get a game as part of a back three, but even that seems far-fetched.
From starting centre-half to the second- or third-choice left-back. Blind's stock has fallen a good distance in 12 months. No one would be surprised if he leaves the club before the next 12 months are out.
4th-Biggest Fall: David De Gea
David De Gea is in brilliant form. There are not many United fans who would swap him for any other 'keeper anywhere in the world. Having De Gea between the sticks sometimes feels like cheating, particularly in games United are dominating. The opposition are already having a tough time creating chances, and then when they do, the Spaniard pulls off a wonder save.
So De Gea's decreasing importance has nothing to do with his individual brilliance. It is just that United need him to be brilliant a lot less than they have done in recent seasons. There will still be games in which he is important, but there have been long swathes in the club's recent history when they have been almost entirely reliant on Spain's No. 1 to keep them in matches.
For the most part this season, the outfield players are capable of pulling their weight. Consequently, a lesser goalie might be able to do the job.
But if you are reading this, Dave, please don't go anywhere. United might not need you as much as they did a year ago, but it is still brilliant having you around. The praises of the mythological broken fax machine that kept him from moving to Real Madrid in 2015 are still being sung.
4th-Biggest Rise: Phil Jones
Now we come to the players who are more important to the squad than they were a year ago. We start with England international—much to Mourinho's chagrin—Phil Jones.
Jones might have what Mourinho told the press was a "proper injury" but has this season managed to stay fit a good deal more than has been the case in recent years. And when he has been fit, he has been living up to some of the potential demonstrated during his youth as an important central defender for United.
His importance to the club will always be limited by how much time he has spent on the sidelines, but he has overtaken Chris Smalling in terms of the central-defensive pecking order, and that was far from inevitable this time a year ago.
3rd-Biggest Rise: Marcos Rojo
If Jones' United career was positively affected by Mourinho's arrival, Marcos Rojo's has been practically transformed. While there is still little or no evidence he is any kind of left-back, his fine work in the centre of defence last season means United fans were celebrating his return to the squad on Saturday in a manner no one would have foreseen this time last year.
It seems reasonable to suggest Eric Bailly and Rojo might just be United's best possible centre-back partnership. He has had a long lay-off and thus might not be able to pick up where he left off. But given this is not about quality but relative importance as compared with last year, Rojo's much-improved reputation earns him a spot on the list.
2nd-Biggest Rise: Anthony Martial
If this were a comparison with November 2015, Anthony Martial's position would not have changed much. The France international had not long arrived at United by then but was already looking a magnificent signing and had proved a difference-maker.
However, by November 2016, the man who had fired United to the FA Cup final with his late semi-final winner against Everton, someone with whom United fans had fallen head over heels in love, had dropped down the pecking order.
Some of that seemed to be perhaps on the player, who had some fairly complex issues arise in his personal life at just about the time Mourinho took charge of United in 2016. Combine that with the change of manager from the man who had invested heavily in him to one with a complex history with mercurial attackers.
All is not entirely rosy this season. There is still a hard-to-shake sense Mourinho does not quite trust Martial in games when structural discipline is at a premium. But the 21-year-old is getting better and better, and his impact this season has been undeniable. He has five Premier League goals and two assists, one Champions League goal and two assists and a goal and an assist in the Carabao Cup.
He is a constant thorn in the side of defenders. Putting him and Marcus Rashford on the flanks against Newcastle may have led to a little tactical imbalance, but it was exciting and caused United's singing section to alter a chant previously used to celebrate Cristiano Ronaldo.
In place of "Viva Ronaldo," they sang "Martial and Rashford, running down the wing, hear United sing, Martial and Rashford." It was a pairing that deserved a chant of its own.
There is evidence Martial has weathered the worst of the Mourinho storm. He has demonstrated over and over again he is a huge talent with a massive future. Given how uncertain things looked this time last year, he has to be a long way up this list.
Biggest Rise: Paul Pogba
A year ago, Paul Pogba was in the infancy of his second United career. It was immediately clear he could have a huge bearing on the club's basic level of quality—right from his return game against Southampton at home on a balmy Friday evening in August 2016.
But a year on, his importance has grown. And grown and grown and grown. Part of it is the natural embedding process as he has resettled into his surroundings and reacquainted himself with life in the north-west of England. That bedding-in process saw his importance develop throughout last season.
Two things happened in the offseason to catapult that growth in importance into the stratosphere. The first is obvious. Signing Matic to be a foil for Pogba proved an instant success. On one hand, Matic's natural defensive instincts and discipline allow the Frenchman more freedom, as many would have predicted.
On the other, though, and more surprisingly, Matic has proved a great on-ball foil for Pogba too. The Serb is more than able to beat a man and draw opposition attention to himself, giving Pogba more room. And his pass-and-move game is strong too. They complement each other brilliantly.
The second was Lukaku's arrival. While Ibrahimovic was important to United last season and scored a lot of goals, he also jammed up the works a bit as far as Pogba was concerned. They often found themselves operating in the same area of the pitch, and while the Swede's movement was often insightful and devastating in key moments, there was not all that much of it. Lukaku, on the other hand, rarely stops moving, and it is Pogba who most benefits from how he stretches defenders.
He was already important this time last year, but now he is essentially the player on whom the edifice rests. When he was out, United struggled. Many warned against too much expectation on his return against Newcastle, but instead United immediately looked brilliant again, and he got an assist and a goal.
Newcastle are not the opposition against whom United will be judged, but the difference Pogba made when compared to, say, the performance at home against Crystal Palace earlier in the season in his absence was vast.
A year ago, he probably was not United's most important player—or at least not everyone had quite realised it yet. Now he is, and everyone paying attention knows it. He easily claims top spot here.