The 26-year-old has been linked with a move to the Partenopei for some time now, as coach Rafa Benitez is set on further strengthening the team in January.
Sky Sports are reporting that an agreement between the two clubs has already been reached, though details over the move have not yet been revealed.
“Antonelli is being defined. The clubs are continuously in contact and [Napoli sporting director Riccardo] Bigon is in contact with the player,” Gianluca Di Marzio revealed during Radio Marte.
“The only thing we’re yet to know is the exact details of the deal. I don’t see any other problems.”
Antonelli has been with the Grifone since joining from Parma in 2011 and has scored two goals in his 58 Serie A appearances for the club thus far.