Walter Mazzarri blasted his Napoli players after they could only draw 1-1 with Catania.
Napoli took the lead against the run of play through Edinson Cavani, but after a sustained period under pressure finally conceded from Alejandro Gomez.
"I am angry, as we didn't play the way we expected," the Coach told Sky Italia television.
"We never seem to do well in this stadium, as we struggled last season as well. Aside from the result, I am not happy with the way the team expressed itself.
"With so many players away on international duty during the break, I saw too many of them put in below-par performances.
"I got even angrier after the equaliser, as we brought out our grit and pride, which we should've done a lot sooner.
"Now we are facing a very difficult run of fixtures. On Thursday there is Liverpool in the Europa League, then Milan on Monday without Paolo Cannavaro, who will be suspended.
"I knew this match with Catania presented hidden dangers and I was not at all satisfied with the approach.
"If we want to target certain ambitions, then we have got to mature quickly and find consistency."