A window of the Juventus team bus has reportedly been broken by an object thrown by Napoli supporters as the squads arrived at the San Paolo stadium for Friday night’s highly anticipated Serie A match.
No Juventus players or staff members were injured during the incident, the ANSA news agency reported.
Napoli fans also launched fireworks, flares and eggs at police, according to ANSA.
"There were moments of tension," Juventus general director Giuseppe Marotta told Italy’s Sky TV. "Honestly, during the trip we were targeted with a bit of everything — pebbles, sizeable rocks, one big enough to break the window where (Ghana midfielder Kwadwo) Asamoah was sitting.
"These acts are deplorable and have little to do with sport," Marotta added. "Napoli Calcio has nothing to do with it, so let’s move on and focus on the match."
The match pits first-place Juventus against second-place Napoli, which is six points behind.