Napoli released a statement condemning Ezequiel Lavezzi's three-match ban, “an extremely serious decision that sets a dangerous precedent.”
The striker and Roma's Aleandro Rosi were both handed three-match suspensions for spitting at each other in an off-the-ball incident during Napoli's 2-0 victory at the Olimpico.
His appeal was rejected on Friday evening and lawyers complained that new video evidence was used.
In the original case, the Disciplinary Commission viewed footage from Sky Sport Italia, whereas the appeal jury also saw a zoomed-in version from Mediaset.
“SSC Napoli are bitter and disconcerted at the sentence from the appeals court who, without even explaining the motivation, confirmed Lavezzi's three-match ban by considering the video evidence to be admissible and beyond reasonable doubt,” read a statement.
“The club consider this an extremely serious decision, purely in terms of legal procedure, that the court wanted to view and presumably base its response upon a different video clip from the one the first decision was made on. It is also a clip not previously seen by the Napoli legal team.
“This move, done with no request to the authorities, risks setting a dangerous precedent.
“SSC Napoli consider that the sporting justice system, in such a difficult moment for our football, has to above all be credible and follow certain, clear guidelines enabling prosecution and defence to protect their rights.
“These are guarantees that in this case were not provided.”