[Mike51]

OBR I know the basics of the BOO rule, but have a slightly different situation. This has not happened to me, but wondering.

A25 should be the batter, but A30 (who is not in the game)comes to the plate. He does not tell the umpire that he is pinch-hitting for A25, just gets in the box and singles. At this point what can the defense do? Is anyone out?

TIA