Juventus midfielder Claudio Marchisio has caused a storm in the Italian media by launching a scathing attack on Serie A rivals Napoli.
The Italy international named the entire Napoli team when asked in an interview whether there are any players he holds in contempt.
"It's not any particular face, but a team, especially after the rough Coppa Italia and Italian Super Cup finals: Napoli," he reportedly told Corriere dello Sport.
"When I am faced with Napoli, something goes off in me."
Napoli have reacted angrily to Marchisio's remarks and demanded an explanation from the player and Juventus.
"Marchisio's comments represent a grave insult towards Napoli and all of Italian football. We are surprised that a player of his stature and who plays in such a prestigious club would say things like that," read a statement on the club's website.
"We hope it is only a misunderstanding and await clarification from the player and from Juventus."
Tensions flared between the two clubs when they met in the Italian Super Cup earlier this season, with Napoli boycotting the post-match presentation ceremony in protest at a refereeing decision.