كتب : Sherif Tarek
The 48-year-old tactician led the Biancocelesti to a historic Coppa Italia triumph in May, but it seems that he couldn't get on with Claudio Lotito.
Lazio president Lotito was unsatisfied with his side's inconsistency throughout last season, and now he is set to appoint a new boss.
"For me it's difficult to tell you that I have interrupted my relationship with Lazio after four years at the club," Rossi announced.
"It is not an easy choice, but one well thought out because lately I have understood that I am no longer at the centre of Lazio's tactical project."
Rossi revealed that he had made his decision to leave the club a while back, but his resignation only materialized in the close season.
"My decision matured a long time ago, but it was not possible to do a Press conference before," he elaborated.
"I arrived on my tiptoes and I will leave on my tiptoes and I intend to do it at Formello where I have felt at home."
Lotito stated earlier on Monday that would start looking for Rossi's successor in the immediate future.
Cagliari tactician Massimiliano Allegri is among the candidates for the Lazio hot seat along with Davide Ballardini.