The former Bayern Munich striker joined Juve only last month.
He told Hurra Juventus: "What counts is the spirit and the desire of the group.
"Perhaps we have something less with respect to Inter and Milan, but the strongest team doesn't always win.
"We need positive results to give us enthusiasm in order to make a jump in quality.
"There are many young players in this team. If tings go right, they can acquire confidence and give an even more important contribution.
"In the future, Juve can return to the golden years."