The 17-year-old scored in both halves as City cruised to a 5-0 victory over Norwich to reach the Carabao Cup last 16.
The Citizens also revealed that the youngster was deployed in an almost completely new role during the commanding victory.
“I asked him in the last three or four days when I decided to play him as a nine - I asked him if he had played (that role) and he said he had never played there before,” Maresca told Man City website.
“He’s very good at finishing so I think it was a good game for him.
“He is a not a 9 for sure but he was good, he is young full of energy, he is strong, he can finish and he made some good decisions, some passes to team mates.
“So I am happy, but again, they are young and we need to go slowly with them.
“We have different competitions. We have many games. We are just at the beginning of the season for sure the ones that played tonight during the season will play Premier League games and Champions League games as the season is so long.