Dropped 3rd Strike

[drh898]

Had this suituation happen last night and I didn't have the answer. Nobody on base, batters swings and misses for strike 3, catcher misses ball which goes to backstop. Since backstop is cinder block and fairly close the ball bounces back quickly and hits batter in ankle. Batter runs to first and is safe.

What do we have? Do we have batter interference and, therefore, an out, which is what the defense claimed? Is the batter "hit by the pitch" and awarded first base? Is the play live and stands as a strike out, passed ball, batter-runner stays at first? (Which is what I did) The batter-runner did not intentionally interfer. The 2 coaches and I talked about it after the game and no one really had an idea of what the ruling should be. Help!!