The Turin-based team have four points out of their opening two games and will visit newly promoted side Crotone after the international break.
Vialli believes the Biaconeri’s domestic hegemony might come to an end and insists coach Andrea Pirlo, who was drafted in to replace Maurizio Sarri, has a tough task at hand.
“I think this is a difficult year for Juventus,” the Italian told La Gazzetta dello Sport. “But this goes beyond the change of coach.
“It’s almost psychological, after nine years, that others have found the countermeasures and that you may feel a little satisfied.
“I don’t know who will win, but I believe that this year the others, in addition to having strengthened, will perhaps feel less than before that Juventus are granted the championship.
“It will be more open.”
The former Chelsea man also lauded Atalanta, a team which could pose a serious threat to Juventus this season, and insists he would hand the Ballon d’Or to La Dea captain Alejandro Gomez.
“I love them as a team and I would have loved to play there,” Vialli added. “They have a style of play that involves you, you score a lot of goals, you make an effort, and you have fun.
“The Bergamaschi play with that spirit that I like: adventurous and courageous.
“Papu has improved over the years, he has become a complete player. He makes the quality and quantity to change the games. He solves them, he wins them.
“Fantastic. But there’s [Lionel] Messi, [Cristiano] Ronaldo, Neymar, [Robert] Lewandowski and you’ll say, oh well, I would award Gomez the Ballon d’Or, but not giving it to any of these is difficult."
