Making sphere rotate from one to another during a bounce

I have a little face on a sphere I would like to rotate from 0 at height of bounce to -90 at bottom of bounce on the x axis. I believe I need Euler angles and a lerp, just cannot picture in my head how it might come together. The idea is as the face bounces up it rotates up to smile at you and as it goes back down rotates forward like its on a persons body facing forward.
New to 3d and was just trying my luck after modeling (poorly) said face in Blender.
The bounce is not using a physics material basically adds a force up when it hits the ground (or a tile)

Just not sure how to approach this.