Man Utd fans spot what Kobbie Mainoo did seconds after coming on vs Man City

Kobbie Mainoo made a swift impact for Manchester United in their defeat against rivals Manchester City . The midfielder earned plaudits from fans with a tenacious tackle just moments after coming on.

The Red Devils faced a challenging journey to the Etihad on Sunday and found themselves trailing 1-0 within 18 minutes, courtesy of a Phil Foden header following a dazzling run by Jeremy Doku . The score remained unchanged until half-time, but just eight minutes into the second half, Erling Haaland confidently doubled City's lead.

In response, Ruben Amorim called upon his bench, introducing young midfielder Mainoo, whose loan request over the summer was turned down by the Portuguese manager. Despite expressing his wish to leave Old Trafford, the 20-year-old demonstrated an immediate grit upon entering the pitch that impressed supporters.

Mainoo joined the action 62 minutes into the game, and within seconds, United had won a corner. However, they lost possession from the set-piece, and City began to launch a lethal counter-attack.

But the young Englishman foiled Pep Guardiola's side's plans, stepping in with a superb tackle to disrupt play. He was powerless when a rampant Haaland stormed through on goal five minutes later to make it 3-0 , but nonetheless, fans were quite smitten with what they saw from Mainoo, reports the Manchester Evening News .

Despite only starting one match this season, United's Carabao Cup loss on penalties to Grimsby Town , and making a brief appearance during the 3-2 victory over Burnley in the Premier League , fans are clamouring for more of young talent Mainoo.

One supporter was quick to praise his performance against City, stating: "Mainoo on the pitch for 20 seconds and already made a successful tackle!" Another fan echoed these sentiments, adding: "Immediately Mainoo wins the ball before City can transition!"

A third fan criticised head coach Amorim, writing: "Mainoo has been on for six seconds and already making an impact. At this point, this manager is the worst."

Meanwhile, another supporter chimed in: "Mainoo is in and already intercepting passes. Proper centre-mid." A fifth continued: "Kobbie 'can't defend' Mainoo with a tackle to prevent a counter already. But he 'can't run' like [Manuel] Ugarte."

However, United's manager remained resolute after the defeat, insisting that he would not alter his footballing philosophy despite a disappointing start to the season .

"The performance was not good," began Amorim. "I'm trying to be rational. I see the record. I understand the frustration and I understand the decisions that come with that. I take the critics. That's it.

"There are a lot of things that you have no idea what happened during these months, but I accept that. When I want to change my philosophy, I will change. If not, you have to change the man.

"And we talk about that every game that we lose. I don't believe in that in the system or whatever. So I play my way and I'm going to play my way until I want to change it.

"I understand how football is and the results dictate the narrative. I see it that way. I know that is hard for people. The fans do not want to hear these things. I don't lie to myself. I see the record and I accept any decision."

Sky has slashed the price of its Essential TV and Sky Sports bundle ahead of the 2025/26 season, saving members £336 and offering more than 1,400 live matches across the Premier League, EFL and more.