Carnevali told Radio Serie A: "I have known De Zerbi since he was a boy, he played in the very youth team for Milan. Sassuolo had to change coach and we liked him as a coach.
"Arrigo Sacchi, with whom I have an excellent relationship, convinced me that Roberto could be the right coach for us and for our type of game, which the club has been trying to carry forward for years.
"He was the best coach we have had? I think of Eusebio Di Francesco, with whom we had many important years, even reaching the Europa League. But every coach has helped us, we have done a lot in recent years and the road is always uphill.
"In our championship you have to be good at keeping up with the top 7 in the table, because maybe the right year can happen in which some of the top teams have difficulties. If we think about Sassuolo it was a miracle, let's try to try again every year."