Changing rotation by code with animator

Hi! I need to change rotation of a rigged character head to rotate as oculus rotate, and i'm doing it through script. Character also have animator component, and blend tree wich allows rigged character to crouch when we change our position. And now when oculus rotates camera character doesn't rotate head, because it's blocked by animator. With animator disabled everything works fine. Is it possible to take control over some parts of a rigged character by code, when he is controlled by animator? Or is there some workaround?