Inter boss Walter Mazzarri says his side suffered from "bad luck" with referee Paolo Tagliavento during the 4-2 loss to Napoli.
The Nerazzurri sufferd their second defeat of the Serie A season at the San Paolo, with Ricky Alvarez being sent off after picking up a debatable second yellow card.
Their other defeat this term - a 3-0 reverse to Roma - also came during a game officiated by Tagliavento and Mazzarri is not happy with the 41-year-old's display.
"There was a series of refereeing mistakes that affected the game," he told the media after the match.
"Alvarez was dismissed with the score at 3-2 in our best period of the match, but there were a lot of fouls more deserving of yellow cards than ours.
"We could have scored more goals had the game stayed 11 versus 11. The incident changed the game.
"Clearly we're unlucky when it comes to Tagliavento. That's our second match this season with him and our second defeat.
"Before the Alvarez sending off there was a handball from [Raul] Albiol that went unpunished, for instance. It must be bad luck.
"A penalty on [Saphir] Taider? We shouted that from the dug-out. There was no foul on [Jose] Callejon because he was offside.
"[Christian] Maggio clearly tugged back [Rodrigo] Palacio? I agree with you and knowing Rodrigo he would have darted towards goal.
"There's not much we can do if they don't give us these penalties."
Inter are now six points worse off than at this point last term, when they eventually finished 19th, but Mazzarri believes the two campaigns cannot be compared.
"The points the side got in the first half of last season came with five players who we didn't have today," he argued.
"The team we have now is the one that managed 19 points from the entire second half of the campaign. Now look at the table and it will read a little differently."