Even hard-to-impress Roy Keane waxed lyrical about the teenage wonderkid in his Sky Sports post-analysis.

“Unbelievable, I don’t want to get too carried away but I’m sure we will,” Keane said.

“He looked like he always had time on the ball and decision-making – when to go long, when to go short. Off the ball as well, what an all-round performance.

“I know the club thinks highly of him. They’ll look to the game today, coming to Everton, for the manager to put him in, he obviously must trust him.

“Listen, good luck to the kid. He was outstanding. It’s a great start for him. Let’s hope he stays injury-free and gets a run of games for Man United because he looked like a Man United type of player today. Nice and brave, a lot of courage, loved watching him.”

An ankle injury in preseason threatened to derail his progress this campaign, but he is now off and running after a five-star performance in the Goodison Park pressure cooker.

A clearance off the line showed he even has a defensive nous to his game.

Mainoo made his competitive debut in the EFL Cup win over Charlton back in January.

A sub appearance in a 3-1 FA Cup win over Reading soon followed, before another late appearance in a win over Leicester City in the league.

But behind the scenes at Carrington there is growing belief the talented kid could be the heartbeat of the club’s midfield for years to come.

The Stockport-born youngster was a key member of last year’s successful FA Youth Cup-winning side, and was rewarded with his first professional contract in May 2022.

He has continued to progress for the Red Devils Under-18’s and Under-21’s, impressing Erik ten Hag who is desperate to integrate the youngster into the first-team more often.

Been with the club since nine

Mainoo began his football at grassroots level with Cheadle & Gatley junior football club.

He was scouted by United aged nine and he worked his way through the youth ranks to establish himself as one of United’s biggest prospects.

In the summer of 2022 , United fans caught a glimpse of the playmaker in action against Altrincham.

BBC Manchester commentator Jonny Crowther called him “different class”.

While last season, he had fans purring during a mercurial display against Carlisle in the EFL Trophy.

10Mainoo celebrates wining the FA Youth Cup with Man Utd’s U18’sCredit: Getty10On United’s preseason tour of the US in the summer Mainoo starredCredit: Alamy10However, an ankle injury in preseason curtailed Mainoo and Utd’s plansCredit: Getty10Manager Erik ten Hag has included Mainoo in Utd’s first team training sessionsCredit: Getty

His vision, anticipation and tackling ability certainly caught the eye.

One fan wrote: “I can watch 17-year-old Kobbie Mainoo’s compilations all day. Man Utd have a player on their hands,” while another said: “Investing in Kobbie Mainoo stocks now.”

A third said: “I watched Kobbie Mainoo vs Carlisle United yesterday. Ten Hag has to include him in the first-team. This is not a joke.

“He’s a baller. All he needs is the physical strength and forget Frenkie De Jong. He can do the job simple.”

Ten Hag has listened

The excitement around Mainoo has seen Ten Hag, known for giving youth a chance at Ajax, take a closer look at the player himself.

He is now a regular fixture in first-team training sessions.

The teenager was first named in a matchday squad for the 0-0 draw against Newcastle last season.

And Ten Hag explained Mainoo, who has been capped by England’s Under-18 team, wasn’t there to just make up the numbers.

The Dutch boss told the club’s official website: “It’s not experience, they [young players] have to deliver.

10Mainoo has risen through the ranks at Old Trafford since the age of nineCredit: Getty10Back in February, Mainoo signed a new longterm contract with the clubCredit: Getty10Mainoo is expected to be the heartbeat of Utd’s midfield for years to comeCredit: Reuters

“You are here to contribute to the team, to the team’s success, and that is why he is here.”

With Casemiro linked to a move away and United failing to entice Frenkie de Jong from Barcelona, Mainoo could be the man to finally fill a gap in midfield they have craved since Paul Pogba’s departure.

Better still, he could go on to become a club legend many believed the Frenchman would.