The Argentine, 29, has scored in both of the Bianconeri's matches so far this season - which sees them with two wins out of two - and Mancini, denying he had problems with Tevez during their time together at Manchester City, stressed the striker's quality.
"The only down I had with Tevez were when he was off playing golf! Joking aside, we did clear the air straight away and he probably wanted to leave the club, but the human rapport with Tevez was always excellent," he told Radio Dee Jay.
"Carlitos can make the difference, as he fights, scores and drags the team forward. He will do very well at Juventus. As a center forward he is extraordinary, because he is sharper and doesn’t have to track back as much. Juventus will do well with him in Europe."
Another forward who Mancini coached in the Premier League, Mario Balotelli, has returned to Italy to great success, though the ex-Inter coach batted away suggestions that AC Milan's star player has grown up and said he has always been remarkable.
"I don't think Mario's matured," he added. "Mario is exactly as he was before, both in good ways and bad, so he has to accepted the way he is. As a player he is remarkable and has unique qualities."
Inter has enjoyed an excellent start to the season under new coach Walter Mazzarri, but Mancini does not believe his former club has the quality to win Serie A this time around.
"Inter have started the season well as a real team, but I really don’t think they can challenge for the Scudetto, at least not this year," the coach continued.
"If president Massimo Moratti does sell the club it will be his decision. On the one hand I’d be happy, on the other it’s a shame because the story of his presidency is an important one."
Mancini is one of the leading candidates to replace Cesare Prandelli as Italy coach, amid rumors that the trainer will step down after World Cup 2014, and the 48-year-old has admitted his interest in the role.
"I don’t know anything about the situation and I respect Prandelli, but it’s only natural that a coach cannot turn down a call from his national team," he added. "That’s true for me and I’d assume for all my colleagues too."