Edinson Cavani stole the show on Sunday as he scored three times to inflict Inter’s 14th league defeat of the season, with Ricky Alvarez briefly restoring hope in the first half as he equalised from the penalty spot.
The win guarantees Napoli at least a third-placed finish this season and qualification to the UEFA Champions League but, although they are seven points clear of Milan in third, Mazzarri affirmed that his side still have work to do if they wish to end the season in second behind champions Juventus.
He told Sky Sport Italia: "We must get the next three points. Nothing is guaranteed. 
"In the next match we will visit Bologna, and they have always been our nemesis. We have to think about finishing the championship the right way, because you can see that Milan are not giving up."
Cavani echoed Mazzarri’s sentiments, insisting the Naples outfit would only rest once second was mathematically secured.
He said: "We will think about that after next Sunday. The next game can be the decisive one.”
With his hat-trick, the Uruguayan took his goals tally to 101 for Napoli, 14 short of Diego Maradona’s record, but he would not make any definitive response as to whether he will be around to overtake the Argentina legend next season.
"For me it is an important milestone," he added. "I will try to get as close as possible in these games that remain, then we'll see. 
"I do not think (about a transfer). I'm focused on the present and on the match against Bologna that can give us the qualification to the Champions League (in second place)."