- A person deliberately touches the ball in motion, or
- The ball in motion hits any equipment or other object (except a ball-marker or another ball at rest before the ball was played or otherwise went into motion) or any person (such as the player's caddie) that a player deliberately positioned or left in a particular location so that the equipment, object or person might deflect or stop the ball in motion.
For a player's right to have a ball or ball-marker lifted before a stroke is made if they reasonably believes the ball or ball-marker might help or interfere with play, See Rule 15.3.
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