Colombia are well prepared, insists Yepes
Jose Pekerman's side begin the Brazil showpiece with a clash against the UEFA Euro 2004 winners in Belo Horizonte.
Favourites to win Group C due to the tournament being played in their native South America, a fast start is crucial for Colombia.
But breaking down Greece - who conceded just six goals in 12 qualifiers - will not be easy, with the resilience of Fernando Santos' team showed in the fact they shipped only once in three pre-tournament friendlies against Portugal, Nigeria and Bolivia.
"The whole team comes with a clear idea of what is Greece," Yepes said.
"We are inspired by the fact of being able to achieve the child's dream… to play a World Cup.
"This is a unique experience."
Colombia will also play Ivory Coast and Japan in Group C.