Rossi got hurt in his side's 1-0 triumph over Livorno on Sunday and underwent tests on Monday that confirmed the Italy international has suffered a sprain in his right knee, the joint in which he has undergone two surgeries to reconstruct cruciate ligaments.
A statement from Fiorentina read: "For the correct evaluation of the entity and prognosis of the injury, in the next few days Giuseppe Rossi will visit specialist professor Richard Steadman, the same surgeon that carried out the second operation of his cruciate ligament in his right knee."
Rossi, who joined Fiorentina from Villarreal last summer, missed almost two seasons after two cruciate ligament injuries while at the Primera Liga club.
The 26-year-old returned to top form this season and leads the Serie A scoring charts with 14 goals.
Rossi was recalled to the Italy squad back in October after a two-year absence and is expected to be included in Cesare Prandelli's World Cup squad if fit.