The former Colombia international told ESPN: "Brazil as a team do not have very much, they are not playing very well.
"It is Brazil, they are five-time champions, playing at home, and that must be taken into account. But I believe that with the level Colombia are playing at, we can dream about more.
"After seeing Brazil's game against Chile, and Colombia against Uruguay, I believe Brazil are the team with most to be worried about. If Colombia play as they have been doing during the World Cup, they can beat Brazil easily."
The teams meet in Fortaleza on Friday.