After my piece in the last Recorder where I explored the rules covering an embedded ball, I was asked twice about the situation where a ball plugs itself in the soil just above the sand line in a bunker. I was unclear on how to answer, but luckily for me if not for him, Ian Poulter faced this exact situation in October of 2020, so there is a very clear answer from the R&A rules official.
The first step is to identify whether the ball is considered to be in the bunker, from which there is no relief allowed. The definition of a bunker specifically notes that ‘a lip, wall or face at the edge of a prepared area and consisting of soil, grass, stacked turf or artificial materials’ is NOT part of the bunker. If it is not part of the hazard, then obviously it is part of the general area of the course, and free relief is therefore given.
Taking that relief, however, may not be as easy. The player must measure one club length from the ‘reference point’ which is the spot directly behind where the ball is embedded. Both the reference point and the spot one club length away must be in the ‘general area’ of the course (i.e. on the grass) and not closer to the hole. If this is not possible, it is not allowed to drop back into the bunker, so the player would unfortunately have to declare the ball unplayable for the cost of one penalty shot.