There is a phrase in the Rules of Golf that is important to remember and apply when you can't see where your ball came to rest—it's "known or virtually certain." The phrase is the benchmark that must be met to proceed as if you know where your ball is, even when you might not.

A simple way to think about the known-or-virtually-certain test is that you must have 95 percent certainty that you know what happened to your ball. In other words, you can have a small degree of doubt, but this is by far the most likely result using all reasonably available information. This might sound like a legal document, but it's a useful way of keeping pace of play and fairness in mind during a round.

Now here comes an interesting dilemma. What if, after applying reasonable judgment, there is an equal chance your ball might be in either one of two areas of the course? We'll give you a scenario to see if you know what to do:

You hit a blind tee shot over a hill where you know there's a red-staked pond (penalty area). You saw it fly over a direct line that would have it tracking toward the very edge of it. Upon reaching the spot where you think it might have come to rest, you find it could be in the penalty area, but it also could be in a cement drain adjacent to the pond. The cement drain is outside the stakes and considered an immovable obstruction.

The question is, if all things are equal in terms of the probability it could have come to rest in either, can you take free relief (from the immovable obstruction) or do you have to proceed under penalty-area options?

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Tricky, right?

The rulesmakers anticipated this scenario and provided a clarification of what to do. Applying Rule 17.1a/1, this is the correct procedure: "If a player’s ball is not found in an area where there is a penalty area and an adjacent abnormal course condition, the player must use reasonable judgment (Rule 1.3b(2)) when determining the location of the ball. If, after applying reasonable judgment, it is known or virtually certain that the ball has come to rest in one of those areas but both are equally likely, the player must take penalty relief under Rule 17."

To clarify, you have to proceed as if it's in the penalty area and not lost in an abnormal ground condition. ABCs include immovable obstructions, ground under repair, animal holes or temporary water.

Tough break, but hopefully you can still salvage a par or bogey.

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