Quote Originally Posted by dreaded_snowman
If a player hits again from the tee and does not declare it a provisional ball (or declare the other ball unplayable), what is the second ball deemed to be according to the rules? A provvy or substituted ball?
If not declared a provisional the second ball is in play. Now if you find your original you cannot play it even if it is playable.

You can declare a ball uplayable anywhere at any time. Even in the fairway if you want.