Fiorentina fans had protested against the club's apparent lack of ambition earlier this summer when they let Montolivo leave for AC Milan on a free transfer, and Della Valle is now happy to have pleased them.
"That was the phone call I had been waiting for on Aquilani," he said at the Viola's pre-season training camp in Moena. "With him we can forget about Montolivo.
"You know we want to get back to where Florence belongs, not forgetting everything we said to the fans. They deserve respect and I will keep my promise."
Fiorentina will begin their Serie A season against Udinese in the weekend of August 25-26.