Gary Neville says Manchester United's have bright futures ahead of him.
But the club legend insists they must be developed into special players by the United coaching staff.
"They've got a few players who could go on to be fantastic, Mason Greenwood, Anthony Martial, Marcus Rashford, Dan James," he said. "They're at that point in their careers where there's promise, real potential, and they show you glimpses of real class.
"They've got to make that jump, I saw it years ago in players like Ronaldo and Nani develop. Wayne Rooney wasn't the finished article when he came to United. They developed into something special. They're young - they frustrated the life out of me for 70 minutes watching them against Sheffield United because I didn't think they gave enough to the team when they weren't playing well.
"I don't have a problem with them not playing well, but you have to contribute when you're not playing well. I didn't see them hassling the defenders, making runs in behind. I saw them ambling around quite a bit and feeling sorry for themselves. The body language wasn't great.
"That gives Ole Gunnar Solskjaer and his coaching staff the footage to go at that front three. There's nothing better as a coach than if you can say to young players, 'this cannot happen but look at this when you're at it and playing well', and that did happen in the last 15 minutes, they were flying.
"All you're doing all along is teaching and coaching, because they are young and you have to give them some leeway for that, but I didn't think they were anywhere near good enough in terms of their attitude for the first 70 minutes."
