Juventus CEO Giuseppe Marotta says Bonucci had to be sold because his motivation to play for Juventus was lacking.
Bonucci was sold to Milan this summer and many believe it is due to the friction between him and Allegri.
But Marotta offered a different explanation, telling Sky Sport Italia: “With Bonucci we accepted his personal and professional desire, which was to join Milan.
“There was the feeling he could go. It was not about incidents so much as motivation that was lacking.
“We have found that keeping players against their will is counterproductive.
“An individual has left, a champion, but many others have remained and there are some talented young players already in place. We made calculated risks.
“I am confident, as we have a group of very strong defenders. And like Bonucci joined us from Bari and became a great player with Juventus, we have some interesting young players ready to do the same.”