Juventus coach Massimiliano Allegri believes Napoli will clinch third place and automatic Champions League qualification.
Genoa, Sampdoria and Lazio are also in the running.
Allegri said: "In terms of quality, Napoli are a little above the rest, but Lazio, Sampdoria, Genoa, Milan and Fiorentina are all capable of getting back into it.
"I think the battle for third will be tough right to the end."