Brazil playmaker Diego signed for the Old Lady late in May from Werder Bremen after prolonged negotiations between both clubs.
Amauri, who also has the Italian nationality, said when asked about his compatriot: "It's something which I am very happy about aside from the question of nationality.
"Diego is a great player and he will help us make a further jump in class. The lad has that winning spirit and a lot of class."
The 29-year-old said he has been helping Diego settle down at Juventus and get accustomed to the new environment in Turin.
"It's true. We often hear from each other. Diego also called me before signing with Juve to ask me for many details about the club, the team and the city," Amauri added.
"I don't know how tempted he was by Bayern. Anyway, I explained to him how well I think of Juventus and Torino.
"From the first moment I arrived here it was as if I found myself at home and I tried to tell Diego that this is the ideal place to give consistency to your own footballing dreams."