Three draws on the bounce had seen Napoli lose ground on league leaders Inter Milan, but the hosts swiftly went about setting that right with a seventh-minute goal to open the scoring.
It was a rare strike for Stanislav Lobotka, who sent a side-foot volley beyond Arijanet Muric via a slight deflection from Tarik Muharemovic - the first time Lobotka had netted since the opening day of the 2022/23 campaign.
To their credit, Sassuolo responded well, and despite almost falling further behind to a Giovanni Di Lorenzo header, the visitors offered some threat going forward.
The Neroverdi ultimately went into half-time just one goal down, although they were inches away from levelling when Aster Vranckx’s header squirmed under Vanja Milinkovic-Savic but not over the goalline.
Sassuolo had gone on to lose each of the seven Serie A games in which they were behind at half-time, but they looked keen to end that unwanted streak here as Milinkovic-Savic was required to beat away Luca Lipani’s low strike after the break.
A lull in proceedings followed that chance, with neither side able to carve out any clear-cut opportunities as the contest drifted into its latter stages.
Late on, a loose pass from Muric was nearly punished spectacularly by Scott McTominay, who saw his venomous effort from range bounce narrowly wide, but that ultimately made no difference to the result as Napoli saw out the points.
Napoli have now won each of their last seven head-to-heads, having still only ever suffered defeat at home on one occasion (W10, D2), with the result keeping them third in the table, six points adrift of Inter.
As for Sassuolo, it’s now seven league games without a win (D3, L4), failing to score in each of their last three encounters. That concerning streak of results leaves Fabio Grosso’s side marooned in midtable, still nine points clear of the drop, but increasingly aware of the chasing pack.
Flashscore Man of the Match: Stanislav Lobotka (Napoli)
