Ex-Manchester United youth coach Harris predicts McTominay will be a game-changer for Napoli

Similar to McTominay, Harris also departed from United earlier this year.

He told the Manchester Evening News: "It's not a coincidence that most of the people who 'make it' have support networks, people who are relaxed around them. His dad, Frank, is a brilliant person and his mum trusted us impeccably with him. If we didn't bring him on a tour, we explained why and there was no fuss.

"Scott was an early developer in terms of his talent, but he stalled a bit because of his growth and injuries, but that's why I think he'll have a career until he's 34 or 35. He looks after himself and because his maturation was so late, he can probably play until whenever he wants.

"And I am telling you now, he will be an unbelievable success in Naples. I spoke to him the other day and he's loving it. I told him when he was moving that they'd love him over there because his DNA is work rate and desire and honestly, I think his career has been very underrated."