Italy managed just a point from their first two Nation League games.
Bernardeschi said, “We need a mentality that brings us back up to where Italy deserves to be, there has to be a core working for the same objective: to restart Italian football.
“This is a good group of players, there are a lot of youngsters with personality and potential, we have a healthy and strong group with which we can start again.
“Obviously a young man cannot be a veteran, it takes a bit of time. What wouldn't be right is criticising a group of youngsters, criticising the fact that they're not ready.
“Roberto Mancini is the right man to start again. He played football, he knows what football is all about. He was a great champion and a great Coach and he still will be.
“We need to give him our confidence and be patient with his work."