(1) No Penalty for Accidentally Causing Ball to Move. There is no penalty if the player, opponent or another player in stroke play accidentally moves the player's ball or ball-marker on the putting green.
The player must:
- Replace the ball on its original spot (which if not known must be estimated) (See Rule 14.2), or
- Place a ball-marker to mark that original spot.
If the player or opponent deliberately lifts the player's ball or ball-marker on the putting green, See Rule 9.4 or Rule 9.5 to find out if there is a penalty.
(2) When to Replace Ball Moved by Natural Forces. If natural forces cause a player's ball on the putting green to move, where the player must play from next depends on whether the ball had already been lifted and replaced on its original spot:
- Ball Already Lifted and Replaced. The ball must be replaced on its original spot (which if not known must be estimated) (See Rule 14.2), even though it was moved by natural forces and not by the player, the opponent or an outside influence (See Rule 9.3, Exception).
- Ball Not Already Lifted and Replaced. The ball must be played from its new spot (See Rule 9.3).
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