Ritchie watched the 18-year-old attacker in action on a number of occasions at the Alexandra Stadium and says it wasn't just his ability with the ball at his feet that stood out, but his awareness on the pitch.
"Even before he receives the ball he knows what he's going to do with it - he's already got that in his mind," Ritchie told MUTV. "That's a big thing for a player who plays in his position. It's important to know what's going around you and even behind you, and he's got that awareness. It's not something you can teach, it's something that inbuilt in you.
"I think he's going to be a very good signing. I've watched him a few times in the flesh and I've been very impressed with what I've seen.
"He has good all-round ability - he's very astute, quite quick, he can play a pass and he knows where the goal is, but the biggest thing for me is his awareness of what's happening around him on the pitch."
Defining Powell's best position will be something, Ritchie feels, Sir Alex and his coaching staff will look at over the coming couple of seasons as they manage his development.
"I think he could play in two or three different positons. I see him as an attacking midfielder but he could certainly do a job up front," he said.
"I think he'd love to play in that little hole just behind the striker where Wayne [Rooney] plays but I don't think he'll be dislodging Rooney just yet!