A Giovanni Simeone hat trick put 10-man Napoli four points behind Juventus in the race for the Serie A title after a 3-0 defeat at Fiorentina on Sunday.
Juventus' late comeback against a 10-man Inter Milan on Saturday salvaged their standing atop the league for another round and put the pressure on second-placed Napoli to respond against the Viola.
But Simeone's goal 28 minutes after Kalidou Koulibaly's sending off complicated things for the visitors at the Stadio Artemio Franchi -- the son of Atletico Madrid coach Diego Simeone racing onto a Cristiano Biraghi through ball and beating Napoli goalkeeper Pepe Reina from an angle.
Simeone put the game out of reach in the 62nd minute when he stabbed home on the doorstep after Reina did well to get a touch on a close range-effort near the goalmouth.
And the Argentine completed his hat trick with the final kick of the game, again beating Reina from an angle.
The loss keeps Napoli on 84 points with just three rounds remaining.