Napoli will enter the new year as Serie A leaders after pulling four points clear of reigning champions Juventus following a 1-0 victory at Crotone.
Juve visit lowly Hellas Verona on Saturday, with third-placed Inter Milan hosting Lazio, but neither Scudetto rival can catch Napoli before 2018 arrives.
It took Napoli only 17 minutes to go ahead through Slovakia midfielder Marek Hamsik, who seized on Allan's pass before shooting beyond Alex Cordaz.
The Azzurri patiently probed for a second goal and in the 35th minute Lorenzo Insigne went close when forcing Cordaz to tip his first-time attempt over the bar.
Crotone were better at absorbing pressure following half-time but soon after the hour Insigne found space and launched a drive that clattered the crossbar.
Substitute Giovanni Crociata gave home fans at the Ezio Scida some reason to get excited late on as he made Pepe Reina punch clear a fierce effort.