The two South American sides face each other in the opening match of the World Cup knockout stages, and the Fluminense forward has indicated that the hosts could look to take advantage of their opponents' lack of height.
The 30-year-old told reporters: "I've talked to our full-backs, our wingers. They are short. With our height, free kicks could be a good weapon for us."
Fred has scored once in three games during the tournament.