setting the arrow

[joec]

Situation: The opening tip goes out of bounds off the visiting team (B). A is throwing the ball in from the side. A is called for a 5 second throw in violation.
When is the possession arrow set? I believe the arrow should have been set when the ball was placed at the disposal of A after the initial tip had been hit OOB. The arrow should be for B. I believe I screwed this up tonight at a varsity game. I set the arrow for A after the ball had been touched on the floor by B after the throw in (by B)following the 5 second violation. Commentary please, would be most welcome and appreciated