Enrico Fedele, the agent of Napoli centre-back Paolo Cannavaro, has claimed that the side "lack the winning mentality" necessary to compete for the title with Juventus.
Coach Walter Mazzarri's men currently sit second in Serie A, four points behind champions Juve, and the player's representative feels the team need to push themselves to succeed.
"They lack the winning mentality and the only way you earn it is over time," he told Radio Crc.
"In order to aim for the Scudetto, Napoli would have to win all [the games], starting from Udinese on Monday.
"As a fan, I hope Napoli can win the title. As a professional in the football world, I say this is just a dream."
However, he says a second-placed finish would already be considered a great achievement for the side, adding: "The truth is Napoli have to lock down this second place.
"That would already be a great success and part of their progress."
Napoli will be looking to bounce back from their 3-0 Europa League defeat at Viktoria Plzen last week, as they prepare for the second leg of the tie on Thursday, February 21.