Both Player A and Player B’s ball were on the putting green. Player A’s ball was considerably off to the right and not in Player B’s line. Player A’s ball had come to rest on a sloping area of the green. Since it did not interfere with B’s line there was no rush to mark his ball.
Player B made his stroke and suddenly gravity caused Player A’s ball to begin rolling down the slope, striking Player B’s ball in motion. Since Player A had not marked his ball, what is the ruling?
This is an interesting situation. Since Player A’s ball had not been marked and then began rolling down the hill, it is considered to be in motion from the previous stroke. Player B’s ball was a stroke on the putting green and was then struck by a ball in motion. This means ‘B’ would replay his stroke with no penalty and ‘A’ would play his at it lies.
If Player A’s ball had come to rest prior to Player B’s striking it, Player B would receive a two stroke penalty in stroke play and play it as it lies. In match play there would be no penalty.
This is explained in Rule 19-5. Remember the big issue is Player A’s ball moving prior to being marked.
Do you have a Rules question you would like answered? Contact me. Gary@thenextgolfshot.com