Aquilani, 42, was relieved of his duties on Monday (November 9), with Sassuolo sitting in 17th following five successive Serie A defeats.
Sassuolo have now confirmed the appointment of survival specialist D'Aversa on a deal until the end of the season.
D'Aversa has had spells at Parma, Sampdoria, Lecce, Empoli and Torino, joining Il Toro while in a relegation fight and managing five wins, three draws and four defeats in 12 games to help them to a 12th place finish.
Sassuolo’s statement reads: “US Sassuolo Calcio announces that it has entrusted Mr. Roberto D'Aversa with the technical leadership of the First Team until June 30, 2027.
“The technical staff will be composed of Salvatore Sullo (assistant coach), Marco Piccioni (technical assistant), Marco Riggio (technical assistant), Paolo Rongoni (athletic coach), Francesco Petrungaro (athletic coach), Andrea Rinaldi (athletic coach), Simone Vignudelli (athletic coach) and Marco Bizzarri (goalkeeping coach).
“The new coach will lead his first training session as the Neroverdi this afternoon.
“The press conference to present the team to the media will be held on Thursday 12 November at 12:30 pm at the Mapei Football Centre.”