President Aurelio De Laurentiis said Napoli are “incapable of honouring the jersey” after “squalid” performances.
The Partenopei crashed out of the Coppa Italia with a 1-0 home defeat to Lazio this evening, losing the semi-final 2-1 on aggregate.
“We have a commitment with the Azzurri fans, who are quite right to be unhappy,” De Laurentiis told Sportitalia.
“From today until the end of the season if we don’t change course and the players are incapable of honouring the jersey on their back, then they are going into a training retreat.
“I hope all of this will serve as a turning point to spark some pride. We have put in some squalid performances that are unworthy of Napoli.
“From today we change tack. We need a training session for the mind, more respect for the fans, the club, the Coach and for themselves.”
Napoli have two draws from their last five games in all competition, scoring just one goal.
It’s their worst negative streak of results since March 2013.
This furious tirade from the President is very different to the approach taken by Rafa Benitez, who insisted his men only lacked "luck" and had played well in recent outings.
De Laurentiis said the training retreat will be for an "undetermined" length of time, so could go on for months.