The 19-year-old is currently on loan with the Scottish Premiership side.
And while McCormack has seemingly confirmed that the youngster has the quality to succeed at the Etihad, he insisted that he has made the right choice joining the Bhoys on loan.
"The sky's the limit for Patrick. He needs to develop and start to learn the game a bit more. He has always had the ability to go past players like they are not there," he told the Record.
"But the Championship is different to most leagues. It's quite physical and there is not much time on the ball. I said to him when he was going to Man City that he was probably going to have to go out on loan and get some experience and return as a better player.
"That’s precisely what has happened. But to be honest there is probably no better club for him to go to.
"Celtic or Rangers in the SPFL attack most games and he can really show what he is good at."
Roberts has shown during his first few months at Parkhead that he has the potential to be a key man under Brendan Rodgers next season, and perhaps could be useful to Pep Guardiola upon his return to the Premier League side.
His six goals helped the Hoops on their way to their fifth league crown in a row, and it was his brace during their clash with Aberdeen earlier in the month that inspired the side to the 3-2 win that confirmed the title.
The prospect's ability to beat full-backs with ease means that he has the skill to create something out of nothing, which will help make Rodgers' side much more threatening next year when they arguably face a trickier task in trying to retain the title.
And as McCormack states, the fact that Celtic will go into most games looking to stay on the front foot should allow the youngster countless chances to get on the ball and show why he is so highly-rated.