Massimiliano Allegri’s side won 3-1 to move six points clear of Carlo Ancelotti’s southerners in front of a record crowd of 39,552 in Turin for a league match.
Gazzetta dello Sport reported that all three Italian Football Federation (FIGC) observers in different parts of the stadium reported hearing Koulibaly targeted by the chanting.
Fans were also reported to have called Napoli coach Carlo Ancelotti ‘a pig’, an insult which goes back to his coaching days at Juventus from 1999 to 2001.
As a result, the ‘Curva Sud’ could be closed for at least one game when the disciplinary report is released on Tuesday.
For more news your way, download The Citizen’s app for iOS and Android.
Download our app and read this and other great stories on the move. Available for Android and iOS.