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[tcannizzo]

Originally Posted by bsnalex

It makes no distinction between a fair or fould batted ball. One could argue that a foul ball that appears to be rolling fair will have a F3 running hard at it to keep it foul because they know they won't have a play at first if it's fair, so the interference remains on the foul ball.

One could also argue that the ball is Fair, until it is declared Foul.
A ball rolling in foul ground is not foul until it settles or is touched in foul territory.