Man United would be MAD to sell Kobbie Mainoo after his Lyon-taming act, writes DANNY MURPHY… Ruben Amorim must do all he can to keep him

Manchester United’s incredible win against Lyon on Thursday night reminded us all it would be madness to let Kobbie Mainoo leave Old Trafford.

For anyone who had forgotten about his talents, his impact during extra time reinforced what we saw so often last season and for England at the Euros: a super-talented midfielder, who is mature, calm and can handle himself on the biggest stage in the biggest games.

Any player who is able to deal with that pressure at such a young age is a terrific asset for Ruben Amorim to have.

I am surprised he has not featured more for United this season, especially with their problems in midfield, although I appreciate he has had injuries. I know Amorim thinks there has been weaknesses in his defensive work in certain games but that’s normal for a young midfielder in the Premier League who is adapting to playing different positions in United’s system.

In my early days at Liverpool, I had Gary McAllister and Didi Hamann alongside me to talk me through games. Without their help, there would have been plenty of matches in which I looked naive in my defensive work.

Amorim’s system has stifled him. Playing central midfield in a 3-4-3 is tough. You must be really disciplined and cover a hell of a lot of ground. It’s clear he doesn’t trust him as much as Casemiro or Manuel Ugarte. He has worked with Ugarte at Sporting Lisbon, so knows he understands what he wants from his midfielders.

It was a reminder of what a super-talented, mature and calm midfielder Mainoo is on his day

There has been speculation about Mainoo leaving United, but Ruben Amorim has to keep him

But I don’t see what Amorim sees when it comes to Mainoo. I think Mainoo is more than capable of playing that defensive role, he just needs some help, leadership and guidance around him. 

I also don’t think he should be pigeon-holed into being one style of midfielder because there is so much variation to his play.

I understand the rumours around him and Alejandro Garnacho needing to be sold for PSR reasons but the equation is simple: are United blessed with an abundance of talented midfielders? No. 

Casemiro and Christian Eriksen are coming to the end of their careers. They let Scott McTominay go. He is exactly the type of player United would be looking to sign if they didn’t have him already.

Even if they sold him for pure profit on the balance sheet, they will have to spend just as much, if not more, to replace his talent.

Mainoo and Garnacho are two talented, hungry players capable of having a big impact for United over the next five years or more, whether that’s under Amorim or any other manager.

If I was Amorim, I would be talking to Mainoo, talking to my bosses, and making sure he stayed. I would still be shocked to see him leave in the summer.

His performance the other night will have provoked a lot of conversations as to why he has not been playing. 

I wouldn’t be surprised to see Mainoo start the semi-final and a lot more matches as the season comes to an end because his talent is there for all to see.