The 2014 tournament provided a major shock on Saturday as Costa Rica stunned Uruguay with a 3-1 victory in Fortaleza, while few expected the Netherlands to defeat reigning champions Spain on Friday - especially not 5-1.
Wilmots is aware Belgium will go into their opening game against Algeria on Tuesday as favourites to claim three points.
Yet he insists there is no danger of the African nation being underestimated when the action gets under way in Belo Horizonte.
"I'm not especially worried because I care more about my team than the opponent but we do work, it's always the same thing," explained Wilmots at a press conference.
"We do a video analysis of the last 10 games, yes the last 10, to know every starting 11. I won't give you my sheets that I've got here, but I know about each player individually and in which system they played.
"So we are ready, we know everything about Algeria, but what I'm interested in is that our players know all about it.
"It's why for the past two or three days, they got the pictures, the strengths and the weaknesses of each player. I prefer to do it over a week, so we (have) time to see, to talk about it.
"If you give them everything the day before the game, it's way too much information, so right after Algeria, they'll have (information on next opponents) Russia for three or four days.
"And it allows our players to come to us, to talk about it with the staff, for players who are interested in that. This helps us to avoid any surprises.''
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