In his column for Gazzetta dello Sport, Sacchi wrote: "The Della Valle (family) brought in managerial competence, economic stability and a futuristic strategy.
"They invested rather than spent and did not make the mistake of assuming they knew everything about the sport, calling instead on the advice of experienced collaborators.
"They are working for the present and the future without draining themselves dry, doing so by focusing on a productive youth system.
However, the step up from fourth to title contenders is a large one, especially now that they are back in Europe.
"Fiorentina could be the big surprise of the Scudetto race, assuming of course that the Champions League does not take too much out of them.
"The club and players don't know much about this competition and could pay the price in Serie A. As for the squad, perhaps they still need a technically-gifted defender."