Napoli pulled level on points with Juventus after claiming a 2-0 win at home to Catania on Saturday night.
Marek Hamsik starred in the game and opened the scoring 31 minutes in before Paolo Cannavaro made the points safe 13 minutes later.
Catania improved after the break and saw a header from Gonzalo Bergessio ruled out due to a foul, but Napoli had done enough.
The hosts dominated proceedings in the opening minutes with Goran Pandev beating two defenders before firing over in the first minute of the match.
Giandomenico Mesto then missed from close range after a superb pass from Edinson Cavani while Pablo Barrientos rifled over in the 28th minute.
Napoli would grab a deserved lead moments later when Hamsik was found at the far post and he side-footed high into the net.
Cavani thumped the crossbar with a free-kick soon after before Hamsik set up their second when he hooked a clearance back across the six-yard area and Cannavaro was first in line to tuck it away.
Catania tried to respond in the second period and despite seeing Alejandro Gomez go close before Francesco Lodi's free-kick was saved brilliantly, Napoli saw out the victory.