#2 Plan B
Belgium will stick to plan A at the start of the match and hope that it will succeed for them as it has done in many games at the 2018 FIFA World Cup.
The plan A consists of keeping possession of the ball, regaining it quickly when it is lost and decisively open the Brazilian defense with the scintillating pace and dribbling ability of its two wingers.
If this doesn't work and Belgium falls behind on Friday, then they will have to revert to plan B which they successfully used in their dramatic 3-2 comeback against Belgium in the Round of 16.
Their plan B is to bring on Fellaini and continuously play long balls towards him or deliver to him a perfect cross in the box for him to score.
Fellaini due to his height and physical strength will win headers comfortably and hence will free the other Belgian attackers like Hazard, Lukaku, and Mertens to run behind the Brazilian defense. Having scored a wonderful header against Japan, Fellaini will be eager to score again for Belgium against Brazil.
The Brazilians should devise a strategy against Belgium's plan B and their defense should be extremely careful against Fellaini.