The former Manchester City coach is full of praise for his old player and says he is a worthy successor to Alessandro Del Piero's jersey in Turin
The Argentine striker played under the Italian between 2009 and 2013, before moving on to the Bianconeri for a fee of around €12 million.
And Mancini is backing Antonio Conte's decision to hand over the No.10 shirt to the 29-year-old on his arrival, saying he is one of the most gifted forwards on the planet.
"Carlos is one of the most talented strikers in the world, with Juve he will be a step above the others in Italy," the 48-year-old told Tuttosport.
"He has just been handed the No.10 jersey, formerly worn by Del Piero. Alex will always be remembered as a Juventus legend but I think Carlos will be a worthy successor. Indeed, he is the right man to wear the 10 on his back."
"Now Conte will not only win the third championship in a row, but is also ready to assault the Champions League. Tevez is about to make a difference in Europe. I can't wait to see him play in our league."
Mancini went on to voice his hope that Serie A can attract more star's of Tevez's ilk in the coming years.
"In recent years, some great players have moved away from our country and for this reason the arrival of Tevez is also be an important signal for Italian football.
"I hope that in the coming years other top players will follow, but I think we have to remain patient before the league can get back to being as competitive as it used to be."