Sunday's 2-1 victory at the San Siro - Napoli's first success at AC Milan since 1986 - was the Azzurri's fifth consecutive win in all competitions and lifted Rafa Benitez's side top of Serie A, level on 12 points with Roma.
"We have done great team work and this is our strength," Benitez said. "We also have quality players that can make the difference.
"We are very happy to have won five games in a row but we can still improve.
"There are still certain things that we need to perfect in order to continue to win more games. But the right character is there and we must continue on this path."
Napoli will be favourites to come out triumphant against promoted Sassuolo, who were destroyed 7-0 by Inter Milan last time out.
Sassuolo are the only team in Italy's top flight who have yet to collect a point.
Roma, like Napoli, also have a 100 per cent record and travel to Genoa to face winless Sampdoria inspired by Sunday's 2-1 derby triumph over Lazio.
The result handed club coach Rudi Garcia success in his first Rome derby.
Inter Milan and Fiorentina will battle it out at the San Siro with both teams
heading into the encounter unbeaten this season.
The Nerazzurri and the Viola are level on 10 points.
Italian champions Juventus have yet to lose this season and will be hoping Fernando Llorente can pick up where he left off on Sunday when they take on Chievo in Verona.
The Spanish striker, who joined Juve this summer from Athletic Bilbao, scored the winner against Verona, his first goal in Italy.
Things are not looking good for AC Milan ahead of their trip to Bologna.
The Rossoneri have won just one of their opening four league games and taken just four points out of a possible 12.
To complicate matters for AC Milan coach Massimiliano Allegri, who is without seven players through injury, Italian striker Mario Balotelli is suspended for Wednesday's game after being sent off against Napoli.
Lazio will be looking to bounce back immediately from their painful derby defeat to Roma when they host Catania.
Sunday's reverse was the Biancoceleste's second loss of the campaign.
Udinese seek home comfort when they welcome Genoa to the Friuli stadium on Tuesday.
Francesco Guidolin's men have lost all of their games on the road so far but remain unbeaten at home.
Torino take on Hellas Verona in Turin inspired by Sunday's 2-1 triumph at Bologna - their first win on the road this season.
Livorno will look to extend their three-match unbeaten run when they face Cagliari in Leghorn.
The Amaranto, who gained promotion to the top flight this summer, won at Sassuolo and against Catania before holding Genoa to a goalless draw last weekend.
Strugglers Parma expect to clinch their first win of the season against Atalanta on Wednesday.
The Ducale club have mustered just two points from their opening four games.