City landed in Portugal on the back of winning all three of their Premier League games so far in 2026/27 and an Erling Haaland double saw the Italian coach seal victory on his UCL bow this season.
However, it was far from straightforward at times for City at the Estádio do Dragão, with goal keeper Gianluigi Donnarumma looking particularly nervous at times.
The former PSG No.1 looked edgy in possession throughout the game, and almost conceded an embarrassing goal when a clearance rebounded off William Gomes, before bouncing just past the post.
He was also cautioned for a reckless foul on Pepe, where only a VAR offside call saved him from conceding a penalty, and Maresca admitted sometimes City need to accept a bad night on the ball for his fellow Italian.
"I think a few times tonight it's not a Donnarumma mistake, it's more the wrong decision to go back to Gigio. Sometimes we go back more than we need.
"We can go back to the keeper when we don't have another option, but the players need to find the other option.
"Against Coventry, there was a mistake where we almost conceded a goal, but that was a mistake from Khusanov to go back to Gigio. I'm very happy with Gigio."