Juventus have appointed former Azzurri boss Spalletti to lead the team until the end of the season.
Spalletti steps in for Igor Tudor, who was dismissed post the Lazio setback last weekend.
Tudor arrived at the club in March filling the shoes of Thiago Motta but departed after seven months after an eight-game winless streak.
Spalletti led Napoli to the Serie A title in 2022-23 then moving on to lead the Italian national team, which missed out on the 2022 World Cup with Mancini at the helm.
He secured their spot in Euro 2024 exiting in the last 16 stage against Switzerland.
Nonetheless, Italy dismissed Spalletti in June after a World Cup qualifying defeat by Norway, with the Azzurri at risk of missing out on a third consecutive World Cup.
Spalletti's managerial career includes Inter Milan, Roma, and Udinese in Serie A and secured two Russian Premier League titles with Zenit St Petersburg.
Massimo Brambilla took interim charge of Juventus during the 3-1 victory over Udinese on Wednesday moving them to seventh position in the league - trailing leaders Napoli by six points after nine matches.
They are 25th in the league phase of the Champions League, having lost once and drawn twice in their opening three matches.