How Make an Vector Follow an Quaternion?

**I have a ray that rotates at all angles through the keyboard input
my player looks all the time for the ball.
I need to do, the axis “X” and “Z” the vector of the player,
follow the Y-axis ray Quaternion
I want to align the player in the direction of the ray
when he’s walking with the ball.

details code:
with this code I get the position and rotation of the player
and I make it look at the ball

void OnAnimatorMove(){

		newPos = anim.rootPosition;
		newRot= anim.rootRotation;
		if (LookAt_Ball) {
		if( info.IsName("WalkBall") && Dist_Player_Ball >0.23
		   || info.IsName("Stantard") && Dist_Player_Ball >0.23)
			Quaternion rotPlayer = Quaternion.LookRotation(newPos - fisicaBola.ArmatureBola.position, Vector3.down);
			rotPlayer.x = 0.0F;
			rotPlayer.z = 0.0F;
			newRot = Quaternion.Slerp(newRot, rotPlayer, Time.deltaTime *speedLookAt);

		if (vecAxisRef.magnitude != 1) vecAxisRef.Normalize();
		newPos.y = 0f;
		transform.position = newPos;
		transform.rotation= newRot;

see this video and see what i am wanting do
i want to align X axis, and Z axis of the player position
in direction of the quaternion of green ray…
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