In 2018, players looking to take relief for an unplayable ball in a bunker under Rule 28 had only two options:

• Drop and play a ball in the bunker itself, either on a line back from the hole or within two club lengths, or
• Taking stroke-and-distance relief, and replaying from the location of the previous stroke. If that previous location was outside of the bunker this was the only way to play the next shot from outside the bunker, at any penalty cost.

This could hurt, sometimes. Once, a few years ago, I found my ball absolutely plugged in the back lip of a bunker. I couldn’t drop back on a line or within two club lengths and remain in the bunker, so my only real options were stroke-and-distance (from 180 yards out) or to play the ball as it lay. I chose the second option, and was quite fortunate to be able to gouge the ball forward about six inches.

In 2019, I would have had a third option to consider. Rule 19.3b allows me to take relief via a “back-on-the-line” procedure to go as far back on the line between the hole and the ball’s location as I want. If I leave the bunker, the penalty is two strokes.

The USGA and R&A’s reasoning for this change is:

• Players often find themselves near the lip (as I did), making the current relief options difficult or impossible to use.
• Use of stroke-and-distance is rarely used for unplayable balls due to the complications and time it takes to return back to the original spot.
• Additionally, once you’ve made a stroke at a ball in the bunker, taking stroke-and-distance relief still leaves a player in the bunker.
• Playing from a bunker is difficult and can almost literally prevent a player from finishing the hole.
• By making the penalty two strokes, this option will only be used in extreme circumstances.

The USGA and R&A say:

In effect, the player who uses this extra relief option will be penalized one stroke for taking unplayable ball relief and one extra stroke for being allowed to take that relief outside the bunker using the back-on-the-line procedure.

This relief will be philosophically consistent with other Rules that provide that, when an obstruction or abnormal ground condition interferes with the play of a ball in a bunker, the player has the option to take free relief within the bunker itself or the extra option to take relief for one penalty stroke by playing from back-on-the-line outside the bunker.

This video explains things really well.