021: Overrunning First Base
7.08(j) Any runner is out when he fails to return at once to first base after overrunning or oversliding that base. If he attempts to run to second he is out when tagged. If, after overrunning or oversliding first base he starts toward the dugout, or toward his position, and fails to return to first base at once, he is out, on appeal, when he or the base is tagged.
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