Argentina-born Retegui scored on his international debut for Italy in the 2-1 defeat to England and found the net again in the 2-0 victory over Malta three days later in Euro 2024 qualifying.
The striker's selection has sparked debate closer to home with Azzurri striker Mario Balotelli previously suggesting Mancini has enough attacking options to call upon from Italy.
But Mancini has been encouraged by Retegui's early development and refused to rule out making similar moves in future.
He said at his post-match press conference: "Retegui is a goalscorer, it's no small thing. It's what we saw when we followed him. He still needs time, but he scores goals and it's an important quality.
"He has the qualities of a centre-forward, but now we have to wait, we have to give him time. He's like a student in a new school: he has to learn everything. But he has unlocked the game, that's no small thing.
"Retegui in Serie A would be a good thing, I think this would give him more strength, he would be able to learn the language and consequently communicate better with his team-mates."
Pressed on whether he would select more non-Italian natives, Mancini added: "Yes, it's a possibility. We have a small percentage of players in Serie A. In Switzerland, 15 out of 20 are natives.
"Belgium is the same. France, Germany, England are among the natives. Up until a certain number of years ago, we had strong players and we didn't need to.
"The others have done things to us, often they've taken away players we've raised and we'll do the same."
Victory over Malta leaves Italy three points behind embryonic Group C leaders England, with the Azzurri not again in action until June's Nations League semi-final against Spain.
"We just have to work and do the right things," Mancini added to Sky Sport Italia. "We always say the same things, we are becoming talkative.
"Work is a big word because there isn't time, we only have time to make them recover and to prepare a little something, there isn't time."