Butt is a big fan of the youngster, but says he needs games to maintain his development.
Butt, who played 387 times for United and has 39 England caps, told BBC Radio Manchester: "Tom can be a great player. His ability is there for everyone to see.
"He's a phenomenal young footballer and he's at the right club to develop, with the right manager, the right coaches and the right players around him.
"He's one of those players who can go on to great things but he needs a good run in the team and to get used to playing week in and week out for a massive club."