Marotta spoke of their summer signing before victory at Chievo Verona.
“To be a real champion, you need quality as a player and a man, which represents Cristiano Ronaldo. He brings a great deal to Juventus and consequently to all of Italian football," Marotta told Sky Sport Italia.
“This is the ninth year of Andrea Agnelli's Presidency and the bar has been raised more and more every season. The players on the field, and on the bench, are all of a high quality.
“Management must target the best possible result, taking into account everything from football performances to cost and marketing."