The 19-year-old made his Rochdale debut against Morecambe in the Johnstone's Paints Trophy on Tuesday, losing 1-0.
But Hill said: "One good thing to come out of the night was Joel's performance and I think he is going to be a top, top goalkeeper.
“He has pedigree and what he has been producing in training was better than what we saw against Morecambe.
“His pass range is remarkable, he has composure and a thirst to win, he reads an opponent very well.
“He is an exceptional talent and I was always going to play him against Morecambe. I've got no reservations, if called upon, to play him in a league fixture, but obviously Josh Lillis is our number one goalkeeper right now."