Juventus moved back to within four points of Inter Milan at the top of the table with an impressive 5-2 win at Atalanta.
Mauro Camoranesi scored twice in rapid succession to give Juventus, who also had three goals disallowed, a comfortable lead at the break.
Jaime Valdes reduced the arrears early in the second half, but Felipe Melo soon restored Juve's advantage.
Fabio Ceravolo brought Atalanta back into it again, but late goals from Diego and David Trezeguet completed a 5-2 win for Ciro Ferrara's side.
Catania hold Napoli
Napoli remain in sixth place after failing to break down Catania. Takayuki Morimoto had a number of opportunities for Catania while Cristian Llama tested the Napoli goal, but the hosts remain second from bottom.
