Rules

Rule 14-5

Ball Moves after Address, Player Strikes Moving Ball

Q.  After the player has addressed his ball and begun the backward movement of the club for his stroke, the player’s ball begins to move. The player continues his stroke and strikes the ball while it is still moving. Is there a penalty?

A.  Yes. The player incurs a one stroke penalty under Rule 18-2b for his ball in play moving after he addressed it. However, there is no penalty for playing a moving ball in this case as the ball started to move after the player had begun his swing.
Below you can view videos related to this Rule.
Video
Club inadvertently hits his ball twice
On this chip shot, T.C. Chen's club inadvertently, but clearly hits his ball twice during the final round of the 1985 U.S. Open.
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Video
Ball be struck at with the head of the club
Rule 14-1 requires that the ball be struck at with the head of the club.
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