Astori, capped 14 times, joined the Milan youth academy and played for Cagliari and Roma before moving on loan to Fiorentina in 2015.
Davide Astori, who played 14 times for Italy as a defender, died in his sleep in his team's hotel ahead of their Serie A clash against Udinese away.
Cagliari turned on the style to hold Inter Milan to a 2-2 draw at the San Siro on Sunday as Fiorentina hammered 10-man Atalanta 4-1 at home to take over third place from Napoli.
Davide Astori is to join up with the Italy Euro 2012 squad as cover for injured veteran centreback Andrea Barzagli it was reported by ANSA on Wednesday.