The veteran coach has called upon Antonio Conte's side to realise their own quality when faced with the continent's best teams
Antonio Conte's side sealed their third straight Scudetto on Sunday thanks to Roma's 4-1 loss to Catania but have struggled to make an impact in Europe.
The veteran boss believes that the time has come for Juve to transform their domestic form to the European stage but is still impressed with their performances over the last few years.
"Juve win because they are the strongest of the last three years," he told La Gazzetta dello Sport.
"They were simply on another level this year and got the better of an extraordinary Roma. Juve are the deserved champions. But now they must make the international breakthrough.
"Juventus must find a dimension to win abroad as well. They lack awareness of their own strength. Outside Italy, they have a psychological security.
"If you find yourself in the Champions League against Real Madrid, Bayern Munich or Barcelona, you have to deal with them as well.
"They could have done more in Europe. Last year, they came up against a strong Bayern, this year they slipped on a couple of banana skins."