The 51-year-old has warned that Champions League qualification is not yet mathematically certain for his side and revealed he will decide on his future at the end of the season
Napoli sit eight points above fourth-placed Fiorentina with just four games remaining, but Mazzarri has highlighted the danger of complacency at this stage of the campaign, particularly given the strength of Sunday's opposition.
“Whatever happens tomorrow I don’t think we will be mathematically certain of Champions League qualification," he told a press conference.
“The goal difference gives us an advantage, but if Milan were to catch us on points then the situation could change. We mustn’t think about that at the moment, nor what the other teams are doing.
“The boys have grown over the course of the campaign, everyone feels important and I doubt the squad is thinking back to our defeat at San Siro in December.
“If you look back at our wins over Atalanta and Cagliari, you see we struggled to get all three points.
"Inter have more important players compared to these teams and will face this game with their blood boiling.
"We need, as always, the perfect performance.”
Mazzarri also took a swipe at the growing media speculation surrounding his future, insisting he will not be drawn on revealing his plans until the end of the season.
“I am discussing many things with director Riccardo Bigon and if [president] Aurelio De Laurentiis arrives then I’ll talk to him too, but I only want to evaluate things when the season is over," he stressed.
"I will start thinking of what to do, then at the end of the year, after the final game with Roma, you will know what I’ll do.
“After five wins and a draw the media want me to guarantee the Napoli project in future, whereas before that run it was the opposite, but it doesn't matter to me as I know how to play the game now.
"When you win, the coach is talented; when you lose, it’s all his fault."
Reports in Italy have suggested Manchester City are considering an offer of €35 million plus Edin Dzeko for star striker Edinson Cavani, while Napoli themselves have been linked with Roma's Pablo Osvaldo, but Mazzarri remained coy on the speculation.
“They are players of the highest level, but I will just say that the football pitch is proof of that," he said.
"It doesn’t require a scientist to know they are talented.”