A real scenario which is causing a bit of discussion, so one for those who know the rules in depth. As follows:
A group of players are playing in a Stableford Competition. Half way down a hole, Player A declares that they cannot now score any Stableford points and therefore they have ‘completed the hole‘ (Rule 21.1b). However they then proceed to play out the rest of the hole ‘as practice’.
On the green, Player B putts and hits Player A’s ball. Both Player A and Player C agree that Player B has incurred a penalty of 2 strokes and must play their ball where it lies. Player B takes the putt from there and holes out to score one Stableford point, having included a 2 stroke penalty.
So the question:
As Player A’s ball was no longer “in play” is it considered to be a ball or a movable obstruction?
If it is a ball then the action taken was correct. However if it is a movable obstruction then the stroke should have been cancelled and replayed. As Player B did not do this they would have incurred a 2 stroke penalty for playing from the wrong place, and possibly an automatic zero points on the hole if this breach was “serious”.
Is the ball which is not in play but at rest on the green a “ball” or a “movable obstruction”? (Another scenario might be if a provisional ball was played on to the green and then the original ball was found).
Please let me know your thoughts and particularly if you can cite any rules, definitions, or clarifications which would help.
Golf Rules Guru 
Hi
What a great question this was, I’m surprised no one commented.
Rule 21.1b(1) advises in the last sentence:
The hole is completed when the player holes out, chooses not to do so or when his or her score will result in zero points.
The Definition of “In Play” opens with the following statement:
The status of a player’s ball when it lies on the course and is being used in the play of a hole
As the player has announced that they can no longer score on the hole then that player no longer has a ball “In Play” on the hole and, as such, no penalty applies under the exception to Rule 11.1a, which states:
Exception – Ball Played on Putting Green in Stroke Play: If the player’s ball in motion hits another ball at rest on the putting green and both balls were on the putting green before the stroke, the player gets the General Penalty (two penalty strokes).
It’s important to note what the rule book means when it speaks of a ball at rest, again, the definition of “In Play” explains this:
When the Rules refer to a ball at rest or in motion, this means a ball that is in play.
Therefore, as Player “B” has not struck a ball that is “In Play”, there is no penalty. As Player A’s ball was not a ball In Play it is deemed to be a Movable Obstruction and player B should have cancelled the stroke and replayed it as per Exception 2 to Rule 11.1b.
The Rules of Golf are just one big game of “Join the Dots”, and if you know your Definitions, of which there are 74, and the additional 42 Interpretations contained within 25 of them, then you are well placed to play the game.
Regards
Fraz
The Golf Rules Samaritan
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Hi Frazer
We had quite a lot of discussion on this question via email which never made it into these comments. As a group we didn’t come to a collective definitive conclusion. I will try to summarise the debate which centred around the definition of “In Play”.
While the first sentence of the definition includes the phrase “being used in play of a hole” and a hole is completed for stableford purposes when no points can be scored. This combination indicates that the ball may not be in play. However, the enlarged definition of “In Play” does not recognise the concept of “completing a hole” but is phrased as follows:
“A ball first becomes in play on a hole:
– When the player makes a stroke at it from inside the teeing area, or
– In match play, when the player makes a stroke at it from outside the teeing area and the opponent does not cancel the stroke under Rule 6.1b.
That ball remains in play until it is holed, except that it is no longer in play:
– When it is lifted from the course,
– When it is lost (even if it is at rest on the course) or comes to rest out of bounds, or
– When another ball has been substituted for it, even if not allowed by a Rule.”
A’s ball has not been holed, lifted, lost, or substituted so must still be “in play” – it would have been very easy to add “When the hole is completed” as one of the “no longer in play” criteria if this was intended.
In addition, it is reasonably common to combine stableford and medal play in one competition. If A’s ball scoring zero points is not in play then this could lead to the situation where Player B would need to take differing actions and return different scores for the medal card and the stableford card – but both are strokeplay competitions!
So perhaps not as clear as your answer??
Kind regards
Stuart
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