by UmpSteve » Thu Jul 29, 2010 10:32 am
No.
A defensive play made by an unreported sub/reentry can be nullified if appealed before a next pitch, and the batter returns with the existing count just prior to that last pitch (same penalty as using an illegal glove, by the way). After batting, the results of an at-bat by an unreported sub/reentry can be nullified and that batter is out, if appealed before the next pitch (similar to batting out of order).
Otherwise, the only result is the player is now reported back in the game.