3. If a ball is hanging on the lip of a pocket and falls into that pocket by itself after being stationary for five seconds or longer, it will be replaced as closely as possible to the position it was in prior to falling. The five-second count does not begin until all balls in play have stopped moving. Whether the shooter remains at the table does not affect the five-second period. 4.
If a hanging ball drops into a pocket by itself while balls are in motion during a shot, the ruling depends on the ensuing action of the balls: a.
If no ball passes through the area originally occupied by the hanging ball, it is restored and play will continue. b.
If the cue ball, before contacting another ball, passes through the area originally occupied by the hanging ball and, without contacting any other balls, either scratches or remains on the table, both the cue ball and the object ball are restored to their prior positions and you shoot again. (AR p. 101) c.
If the shot is legal and any ball passes through the area originally occupied by the hanging ball, including the cue ball with or without scratching, and any other balls are contacted by such a ball at any point during the shot, a referee will attempt to restore the position prior to the shot and you shoot again. If restoration is not possible, the game will be replayed with the player who broke the game breaking again. (AR p. 101) d.
If the shot is illegal because the cue ball first contacts an illegal object ball before it or any other ball passes through the area originally occupied by the hanging ball, it is a foul. The incoming player accepts the object balls in position. If the hanging ball is designated by specific game rules as the game winning ball it must be restored, otherwise it is not restored.
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