Napoli players will remain sequestered at the club's training centre until Sunday following a run of poor results, club president Aurelio De Laurentiis has said.
Carlo Ancelotti's side have not won for three matches in Serie A and Saturday's 2-1 defeat to Roma saw them drop to seventh in the Serie A table.
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De Laurentiis has decided to take the squad into ritiro -- a fairly common reaction to a poor run of form in Serie A, where players remain on lockdown at the club's training centre for a pre-determined length of time.
"The players will be in ritiro until Sunday, before the call ups for their relevant national sides," De Laurentiis told Radio Kiss Kiss. "Ancelotti is a great manager and a gentleman.
"I have no reason to expect anything more from him. The problem, as far as I am concerned, can only be solved within the group, in the sense that it is not a job which relies on a manager but a blend.
"The players need to find the motivation not just to take on Liverpool or Salzburg, where they have reached their level, which is the reason they were bought and [shows] how they have matured in recent years."
Speaking ahead of the Champions League clash with FC Salzburg, Ancelotti said he was not on board with the decision to go into ritiro.
"The club have taken the decision and we will accept it," Ancelotti said. "But if you ask me whether I agree with it, I would say no."
Napoli have won once in the league since Sept. 29 and recently lost a 2-1 lead to draw 2-2 against Atalanta late on, moments after the referee failed to award them a penalty for a foul on Fernando Llorente.
The controversial penalty decision was even debated in the senate in Italy and De Laurentiis was again critical of the standard of refereeing in Serie A.
"Referees should be managed by the league," he added. "They should all be young, foreign and well paid.
"After three grave errors, they should be taken out of the firing line."
Towards the end of last season, Milan players were ordered into ritiro, while Roma had also done the same earlier in the campaign.