The French star claims Mancini might have walked the walk by steering City to the title two years ago but Pellegrini's ability to talk the talk will be more successful long-term.
Nasri said: "Pellegrini is someone who talks with the players so it is always good for the players to know what's he's doing - if he's good or if he's wrong.
"What I like about him is he talks about everything outside football as well, about how you are in your life.
"It's pretty important for a manager to do this kind of thing. It's a kind of psychology.
"He's a bit like Arsene Wenger in the way he works. It's the same kind of training, the same attitude but the difference is he's not scared to stop the training when something's wrong.
"That's interesting for us because he wants us to play with a principle and to understand, so it's important for him to talk to the players."