Juventus have named ex- Azzurri boss the veteran manager to take the helm for the remainder of the campaign.
Spalletti steps in for the Croatian manager, who was sacked after the Serie A side's defeat by Lazio recently.
Tudor had joined the club in March as Thiago Motta's replacement but departed after seven months after an eight-game winless streak.
Spalletti guided Napoli to the Serie A crown in 2022-23 before taking charge of Italy, which missed out on the 2022 World Cup during Roberto Mancini's tenure.
Under his guidance, they made it to Euro 2024 where they were knocked out in the last 16 by Switzerland.
However, Spalletti was sacked by Italy in June post a qualifying defeat against Norway, putting Italy in danger of missing a third straight World Cup.
Spalletti has also managed Inter Milan, Roma and Udinese in Serie A and won the Russian Premier League twice with Zenit St Petersburg.
Juventus were temporarily led by Massimo Brambilla in the midweek 3-1 triumph over Udinese placing them seventh in the Serie A standings - six points behind leaders Napoli after nine games.
Their Champions League campaign sees them in 25th place in the group stage, with one loss and two draws in their first three games.
