Napoli fans pelted the Juventus team bus with eggs, bottles and rocks, smashing the window where Kwadwo Asamoah was sat.
The Bianconeri arrived at the Stadio San Paolo ahead of tonight’s Serie A match, which kicks off at 19.45 GMT. Click here for the line-ups. 
There was a police escort for the team bus on its journey from the hotel to the stadium, but that did not stop a group of hooligans throwing objects as it travelled.
Reports suggest it was pelted with eggs, but also bottles and some fairly large rocks.
Juventus director Beppe Marotta confirmed the window was smashed where Asamoah was sitting on the bus.
The Ghanaian is not in the starting XI, as Federico Peluso was preferred for the left flank.
“It was not a relaxed journey,” admitted defender Andrea Barzagli on Sky Sport Italia.
“Now we must concentrate on the match, which is better. It will be a game that counts for a great deal and means a lot to us.
“Antonio Conte fired us up with his usual words.”