Lazio brushed aside their dismal home form in Serie A when goals from Ciro Immobile and Luis Alberto gave them a 2-0 win over Napoli on Sunday.
The hosts scored from their only two shots on target as they notched their second win in seven home league games this season while Napoli slumped to a second defeat in five days after losing 1-0 at Inter Milan on Wednesday.
Napoli stayed fifth with 23 points, eight behind leaders AC Milan, while Lazio are eighth with 21.
Immobile volleyed against the crossbar in the sixth minute and three minutes later out jumped two defenders to open the scoring from Adam Marusic's cross, his eighth Serie A goal of the season and his 13th in all competitions.
Lazio goalkeeper Pepe Reina, facing his former club, saved from Fabian Ruiz and Piotr Zielinski as Gennaro Gattuso's side tried to battle their way back into the game.
However, the visitors also produced few scoring chances despite having 57% of the possession and Luis Alberto curled in a second for Lazio in the 56th minute after Napoli lost the ball in midfield.