The 67-year-old veteran ended his second stint with the capital club after one season, which concluded with a Coppa Italia final defeat by Inter Milan and a ninth-place finish in Serie A.
His brief return contrasted sharply with Sarri's initial three-year tenure from 2021 to 2024, during which he had guided the side to a runners-up finish in the league in 2023 before leaving due to family matters.
Italian media reports said that Sarri will take over Atalanta in the near future, while former Italy boss Gennaro Gattuso is set to take charge at Lazio.
The change comes days after AC Milan parted company with manager Massimiliano Allegri, a day after the Serie A season ended.
More to follow.