After Madrid beat United 2-1 in the second leg of the Champions League Round of 16 (winning 3-2 on aggregate), Ronaldo felt that the Spaniards had forced Ferguson to be quiet.
"Real Madrid shut his mouth for me," he told reporters in Brazil.
After Ferguson made the comments earlier this week, Ronaldo responded by saying that the Scottish tacticians words were disrespectful.
"I respect his opinions, I'm not pretentious as to expect that everyone will think I'm the best," he told reporters.
"I'm happy for what I achieved in football and for having been chosen as the best in the world.
"I feel sorry for the disrespectful manner in which he referred to me, it's something that's not good for someone of his position."