When Amad Diallo is this good, who needs Marcus Rashford & Alejandro Garnacho? Winners & losers as ruthless Man Utd boss Ruben Amorim lands second major blow on Pep Guardiola with Erling Haaland stuck in big-game rut

The coach showed his authority by dropping a bombshell in his matchday squad as he left out Rashford and Garnacho. The decision almost backfired when Mason Mount pulled up injured and when his side fell behind the only attacking options Amorim had were Joshua Zirkzee and Antony. But by making an example of Rashford and Garnacho, the Portuguese showed that he is not to be messed with.

Amorim then produced a clear tactical plan, targeting Kyle Walker with lots of balls to City's right-hand side and refusing to let their hosts dominate possession. United may have fallen behind but they did not let their heads drop and stuck to the plan, pulling off a remarkable escape act in the end. City played their part in their own downfall but the importance of the victory cannot be underestimated.

Amorim has now beaten Guardiola twice in the space of six weeks, having also masterminded Sporting CP's 4-1 Champions League win over City, and he is the first United boss since Ole Gunnar Solskjaer to win at the Etihad. The victory not only reduced the gap between City and United in the Premier League table to five points, it showed that if the players follow Amorim's orders, they can achieve great things together.

Gvardiol's goal was the fourth United have conceded from corners in their last three Premier League games. Moments later a concerning graphic emerged, showing that the team have let in the second-highest number of goals from set pieces in the league (only behind relegation-threatened Wolves) and have the highest proportion of the goals conceded from set pieces (42 percent).

The problem pre-dated Amorim's arrival but despite the efforts of specialist set-piece coach Carlos Fernandes, it seems to be getting worse. Amorim has made the team much more secure in open play than under Ten Hag, but that improvement is being cancelled out by their vulnerability from set pieces. Opposing teams are going to continue to target United from set plays and it will take lots of work on the training ground to put things right.

Amad was criminally over-looked by Ten Hag but he has quickly emerged as the most important player in Amorim's first month in charge and this performance could be the making of his Old Trafford career. He has contributed to six of the 14 goals United have scored on the Portuguese's watch and even when he was not performing at his best at the Etihad Stadium, he always looked like the player most likely to make a difference.

And so it proved. Arsene Wenger told Mohamed Salah that the thing that separates the very best players from the good players is an ability to stay in a game and keep going until the final whistle. Amad did just that, brushing aside a disappointing first half - in which he strayed offside twice - by making the difference in a matter of minutes. The Ivorian had been probing makeshift left-back Matheus Nunes throughout the game and finally got the better of him when he switched wings, forcing the Portugal international to foul him in the area.

Amad looked bruised by the challenge but he kept going and produced a magical touch and finish under pressure from Ederson to win the game. On a day when Rashford and Garnacho were singled out by their coach, Amad demonstrated that he is the best winger at the club right now. United must now make it clear how important he is to them by tying him to a new contract.

Walker is experiencing one of the worst moments of his career right now as one of the main culprits in City's dreadful spiral of results. So the last thing he needed to do was further embarrass himself with his shameful play-acting when he locked heads with Rasmus Hojlund after fouling the Danish striker.

The City captain tried his hand at acting last year in a hilarious imitation of Leonardo Di Caprio in the Wolf of Wall Street but no one was fooled by his theatrics. Walker was branded an 'embarrassment' by Roy Keane and Hojlund dug into him after the game with a cheeky post on Instagram. He was cautioned but he was extremely fortunate not to have picked up two yellow cards, one for the foul and one for trying to get a fellow professional sent off.

Amad stole the headlines and the points but Maguire deserves an equal amount for his role in the victory. The £80m man was close to joining City before he chose United back in 2019 and although he will probably never justify the transfer fee invested in him, he reminded everyone of his quality and reliability with a defensive masterclass.

Maguire had Erling Haaland in his pocket and his pro-active, intelligent defending also ensured Phil Foden and Kevin De Bruyne could not do any damage either. The former captain had only started one previous game under Amorim, when he was hooked before the hour-mark. The coach, however, knew that there was only one man for the job.

"Maguire is perfect when you play with three defenders," Amorim raved. "The striker that they have [Haaaland] with the long balls, you need to be really strong. It was perfect for him, but not just Harry. All the guys defended really well. They were really focused and that is the key to play better. I think he did a great job and also his teammates did a great job."

The Norwegian usually relishes playing United for obvious reasons, given his father's history in the fixture. He had scored six goals in his previous four Premier League games against the Red Devils but this was his worst display in a derby by far.

He only had one shot during the game, which was blocked, and looked lost for much of the game. It followed an abysmal performance against Juventus on Wednesday and was another demonstration of his ineffectiveness in big games. Arsenal and Chelsea are the only top-level opponents he has scored against this season, drawing blanks against Inter, Liverpool and Tottenham before his two toothless displays this week.

After making a breathless start to the season with 10 goals in his first five Premier League games, the striker has just three strikes in his last 11 matches. He has also lost ground in the race for the Golden Boot, currently tied on 13 goals with Mohamed Salah, with Cole Palmer right behind him. City's problems clearly run much deeper than him, but he is in a real rut.