Napoli led the way for parts of the season, but following a couple of unsuccessful results, and Juventus' 21 game unbeaten run, they find themselves 6 points adrift of the top of Serie A.
Despite this gap, and the fact they will be without star striker Gonzalo Higuain for the following four games, Del Piero insists we would be foolish to rule Maurizio Sarri's side out of the race just yet.
The title is absolutely not won. Anything can still happen," he told La Gazzetta dello Sport.
"Napoli are having an extraordinary season, playing exciting football and they are sure to respond.
"I really admire the work of Sarri and I wouldn't be surprised if Juve lost the Scudetto."
With seven games remaining, the smallest slip for Juventus could lead to a very exciting finish.
Juve travel to the San Siro to take on AC Milan on Saturday, while Napoli face bottom side Hellas Verona on Sunday.