Goals from Stephen Ireland, Emmanuel Adebayor and Jo ensured City eased to a routine win.
Mancini told the club's official website: "The main thing is that we came through without any serious injuries and that is important.
"I am sure the players were glad to get into action after two weeks of hard work and I thought we did well against a side that is progressing in the United States and which was well prepared and fought hard all night.
"It was good for the young players to show what they could do. We used the defensive ones in the first half and the midfielders and strikers in the second half.
"This was only a first step but a big one on the way to the start of the Premier League season."
Source: PA
Source: PA