The Blues were battling winners against Servette in a Europa Conference League qualifier.
While they did win 2-0, many fans were frustrated at the way the team was performing.
Maresca stated about half-time boos: “The message is quite clear: We are in a moment where we are learning how to manage the game. Probably in some moments, the right thing was to do exactly the same thing but on the other side.
"The intention to keep the ball is the correct one, especially when you are 2-0 up. So the intention is good but probably where is not good. We tried to manage the ball in the last 10 or 15 minutes on our side but we need to try to do exactly the same on the opposite side.
"I can understand but the important thing is to win the game. Clean sheet, we did nine changes, we had players like Renato (Veiga), Axel (Disasi), Pedro (Neto) and even Marc (Guiu), Filip (Jorgensen), it was his first official game, so many good things."
On his players learning during games, he added: "I think all of them need more time to know the system better. For sure, 100 per cent. But tonight was also not easy for some of them in terms of physical condition.
"As I said, the intention of the players to keep the ball is a good one. But sometimes we need to do the same on the opposite side."