Leicester were largely dominated in a goalless first half at the Britannia Stadium before Pearson opted to introduce to introduce the 34-year-old former Argentina international, who joined on a free transfer after being released from Inter.
And with the midfielder a commanding presence, the Premier League new boys managed to secure their first win since returning to the top flight thanks to Leonardo Ulloa's solitary goal.
"We didn't feel as though we played with the same sort of control as we have in our other games so far this season," said Pearson.
"There's always an element of risk when you play players who have been on international duty and travelled the distances some of our lads have done, but at least we stayed in the game.
"The changes at half-time certainly allowed us to get a little more control – we changed the shape and a couple of personnel in midfield. It allowed us to get back into the game."
One of those midfielders, Cambiasso, was singled out for special praise.
"His game management is exceptional,” said Pearson.
"He's not been the success he has over his career without showing qualities not just with the ball, but in terms of his organisational skills. He was a very important influence on the game in the second half.
"He's a good communicator. His English is better than he thinks it is. Communicating on a football field, some people are very, very good at it and some people aren't, and he is a good communicator.
"I think the 45 minutes for him was about right in terms of an introduction to English football, and I'm very pleased he's played his part in what is a very important win for us.
"But it wasn't just him but the whole team. We functioned better as a team [in the second half].
"It wasn't an easy game, but I was very pleased with the commitment in the second half towards getting the three points."
