Ruben Amorim has two unexpected Man United undroppables - thanks to Ruud van Nistelrooy decision

As Ruud van Nistelrooy walked towards the Old Trafford tunnel with the acclaim of the Stretford End ringing in his ears, he looked like a man pleased with his work. Over to you, Ruben. Follow that.

This morning, Ruben Amorim will change his employer on LinkedIn and get to work trying to breathe life into a football club that has rediscovered its fight but continues to languish among the also-rans domestically and in Europe. His CV shows he did a similar job at Sporting, and he leaves Lisbon having transformed their fortunes. A statue awaits if he does the same in Manchester.

He will take over a team in a much better position than two weeks ago. Van Nistelrooy has picked them up and hands over a team in form and with confidence restored. After three wins and a draw, the former United No. 9 steps back from frontline duties with the best win percentage of any manager in the club's history. Joking aside, Van Nistelrooy has done what was asked of him, rounding off his spell in the hot seat with a 3-0 win against Leicester City.

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At some point today, Amorim will drive down the long path towards Carrington and herald the dawn of a new era. The 39-year-old is perhaps United's most existing appointment in the 11 years since Sir Alex Ferguson took his leave. He has taken 258 games in Portugal to end up at Old Trafford. By contrast, Erik ten Hag had managed 437 professional matches before he got the United job.

Amorim also has a more defined style than most of those who have gone before him. He is wedded to a back three, and it would be a surprise if he unveiled something new now that he has one of the biggest jobs in the footballing world. Ever since his appointment was confirmed, the question has been who will fit into that approach and who won't. Who will be the winners and losers from Amorim's arrival?

Van Nistelrooy has fulfilled his brief in terms of results and rebuilding confidence, but there have been no significant tactical developments from the days of Ten Hag and a 4-2-3-1. No wing-backs, no twin No. 10s, and no back three. The revolution will begin at Portman Road in two weeks. Rarely will a United teamsheet be scrutinised more heavily than that one.

One area where Amorim does have strength is in midfield. He has tended to play two deeper central midfielders and then either one or two No. 10s behind a striker. Options abound with Manuel Ugarte, Casemiro, Kobbie Mainoo, Christian Eriksen, Mason Mount and Bruno Fernandes.

The latter, who scored a goal on a milestone appearance once again on Sunday, will take one of the attacking slots. Further back, Mainoo fits the profile of an Amorim player, but injury has struck at the worst possible time. Instead, Van Nistelrooy's parting gift to his replacement might be the partnership between Ugarte and Casemiro.

The Uruguayan, a £42m summer signing from Paris St-Germain, will have been delighted to see Amorim get the job. He played 85 games under him at Sporting, and after a false start to his United career under Erik ten Hag, he is settling in nicely.

It looked clear Ten Hag didn't fully trust him in a holding midfield role, but he has started all four United games under Van Nistelrooy and is improving by the week. Interestingly, he has also started all four next to the man he was signed to replace, Casemiro. The Brazilian has enjoyed something of a renaissance since his horror show against Liverpool, and he has benefitted from a close relationship with Van Nistelrooy.

They were aggressive in winning the ball back in deep midfield positions, with Ugarte particularly destructive out of possession. The 23-year-old also zipped some excellent passes around a slick surface, breaking open the game with a ball to Noussair Mazraoui that led to United's second.

There are puzzles for Amorim to solve. United don't have any obvious wing-backs, and one of the prime candidates for a potential role on the right is out of form, in Diogo Dalot. At Sporting, he has had a ruthless striker scoring at a frightening rate, but Rasmus Hojlund looks a long way short of Victor Gyokeres, and his hold-up play has been particularly poor of late.

But in midfield, he has a base to work from, metaphorically and literally. Amorim wants energy and aggression from his midfield, and at the moment, the two South Americans are providing that. Mainoo might have a say long-term, but Ugarte and Casemiro will surely be two of the first names on that highly anticipated team sheet at Ipswich.