Carlo Ancelotti skipped UEFA media duties and his players reportedly failed to return to a training camp, which may lead to club discipline.
Napoli have threatened to punish their own players after Carlo Ancelotti's first-team stars apparently abandoned a week-long training camp.
Tension is building in Naples following a poor run of form that has seen Ancelotti's side win just twice since September, and the experienced head coach risks a UEFA fine after failing to hold a news conference after Tuesday's 1-1 draw with Salzburg in the Champions League.
Furthermore, widespread reports have said the Napoli players went to their homes after the game in an act of open rebellion, rather than return to a training retreat at nearby Castel Volturno that club president Aurelio De Laurentiis is thought to have ordered.
De Laurentiis spoke with his lawyers and Ancelotti on Wednesday, according to La Gazzetta dello Sport, before the club released a statement that indicated punishments could be coming.
Napoli's statement said: "With regard to the behaviour of the first-team squad on Tuesday night, the club announces that it will do everything in its power to protect its economic interests, assets, image rights and disciplinary interests.
"The club would also like to make clear that it has entrusted first-team coach Carlo Ancelotti with decision-making responsibility as regards the first-team training camp.
"There will be no more press statements for the foreseeable future."
Napoli, who finished runners-up to Juventus last season in Ancelotti's first campaign at the helm, are seventh in Serie A.
Despite some reports suggesting Ancelotti is on the brink of being sacked, the head coach has received backing from captain and striker Lorenzo Insigne.
"We're a close-knit group and that's down to the coach as he maintains calm and has tried to take the pressure off us in this difficult spell," Insigne said.
"We're grateful to him and we all want to perform well for him. He helps us so much and he deserves success.
"We must look forward and think positive. Everything is in our hands and we're determined to wrap up qualification in our two remaining games."