By FOX Sports Staff
The Neapolitans registered a 2-0 win over Catania on Saturday but threatened to ease off in the second half on the night.
Catania even scored a goal in the 47th minute but it was ruled out after Juan Camilo Zuniga was fouled within the box.
Mazzarri scolded his side for taking the result for granted after Marek Hamsik scored and setup another within a dominant first half.
"We should've killed it off with a third goal," he told Sky Sports Italia.
"I cannot change my attitude by looking at the table.
"Our results come from battles like the one we had today [Saturday] and we must not get distracted.
"We need to remember every game is a battle.
"We did well not to panic during some moments under pressure today, though we still need to mature in those terms.
"We should've killed it off with a third goal, even if at times the state of the pitch penalises us. If you want to win in modern football, your strikers have to work hard and help out when the opposition has the ball."
The match was also Gianluca Grava's first start of the season as regular defenders Christian Maggio, Hugo Campagnaro and Miguel Angel Britos missed the game due to injuries or other reasons.
Mazzarri commended the 35-year-old veteran for his patience as well as a good performance at the Stadio San Paolo.
"I want to compliment Grava, a champion who was incredible and kept Alejandro Gomez quiet despite not playing for a long time," he concluded.
Juventus could go three points clear of Napoli once more with a win at Chievo later on Sunday.