Most of us think that we know what the word ‘replacing’ means, but in the Rules it does not necessarily mean the obvious. For example, Rule 18-1 states;
If a ball at rest is moved by an outside agency, there is no penalty and the ball must be replaced.
There is no problem with this requirement, providing the exact lie and location of the ball that was moved is known. However, very often this is not the case, as in the scenario where a player is 150 metres away from where their ball has come to rest in the rough and they witness someone from another group playing it by mistake.
In most cases it is not possible for the player to be sure of the lie of their ball in the rough, or precisely where it was at rest. If the player does know the spot, but the lie has been altered (e.g. a divot hole has been made by the other player when making their stroke), Rule 20-3b is relevant and the ball must be placed in the nearest lie most similar to the original lie (check the wording of this Rule for the full detail). If it is impossible to determine the exact spot where the ball is to be replaced, Rule 20-3c requires that the ball must be dropped as near as possible to the place where it lay (again check the wording of this Rule for the full detail).
This subject leads to another possible area of confusion, the difference in the Rules of Golf between placing and replacing.
Placing and Replacing
One way of remembering the distinction between placing and replacing is through this convenient summary;
Placing is putting a ball on a spot for the first time;
1) Putting the original ball on a new spot (e.g. when the original lie has been altered, Rule 20-3b, as above, or when ‘Preferred Lies’ applies).
2) Putting a substituted ball on a new spot (e.g. Rule 20-3b when the original ball has been lost).
3) Putting a substituted ball on the original spot (e.g. Rule 18-1, when the ball at rest was moved by an outside agency and has been lost).
Replacing is everything else;
1) Putting the original ball back on the original spot (e.g. on the putting green, or when it has been lifted because it interfered with another player’s stroke).
2) Dropping the ball (or a ball), required to be replaced, as near as possible to an estimated spot not precisely known (e.g. Rule 20-3c, as above).
So confusingly, there are some situations in the Rules of Golf when replacing a ball may mean dropping it at the estimated spot, as in Rule 20- 3c when the player does not know the exact spot where there ball was at rest.
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