The Brazilian was a late drop-out from the champions' squad, with Spanish media reporting he is suffering muscular discomfort in his left leg.
Kylian Mbappe is expected to lead the line for Madrid, second behind leaders Barcelona, with Jude Bellingham and Brahim Diaz in support.
Vinicius Junior is also out injured but should return when Champions League holders Madrid face Atalanta on Tuesday, bidding to overcome a poor start in Europe.