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25-1. Abnormal Ground Conditions
• a. Interference
Interference by an abnormal ground conditions occurs when a ball lies in or touches the condition or when the condition interferes with the player’s stance or the area of his intended swing. If the player’s ball lies on the putting green, interference also occurs if an abnormal ground condition on the putting green intervenes on his line of putt. Otherwise, intervention on the line of play is not, of itself, interference under this Rule.

Note: The Committee may make a Local Rule stating that interference by an abnormal ground condition with a player’s stance is deemed not to be, of itself, interference under this Rule.

• b. Relief
Except when the ball is in a water hazard or a lateral water hazard, a player may take relief from interference by an abnormal ground condition as follows:

  (i) Through the Green: If the ball lies through the green, the player must lift the ball and drop it without penalty within one club-length of and not nearer the hole than the nearest point of relief. The nearest point of relief must not be in a hazard or on a putting green. When the ball is dropped within one club-length of the nearest point of relief, the ball must first strike a part of the course at a spot that avoids interference by the condition and is not in a hazard and not on a putting green.
  (ii) In a Bunker: If the ball is in a bunker, the player must lift the ball and drop it either:
    (a) Without penalty, in accordance with Clause (i) above, except that the nearest point of relief must be in the bunker and the ball must be dropped in the bunker, or if complete relief is impossible, as near as possible to the spot where the ball lay, but not nearer the hole, on a part of the course in the bunker that affords maximum available relief from the condition; or
    (b) Under penalty of one stroke, outside the bunker, keeping the point where the ball lay directly between the hole and the spot on which the ball is dropped, with no limit to how far behind the bunker the ball may be dropped.
  (iii) On the Putting Green: If the ball lies on the putting green, the player must lift the ball and place it without penalty at the nearest point of relief that is not in a hazard, or if complete relief is impossible, at the nearest position to where it lay that affords maximum available relief from the condition, but not nearer the hole and not in a hazard. The nearest point of relief or maximum available relief may be off the putting green.
  (iv) On the Teeing Ground: If the ball lies on the teeing ground, the player must lift the ball and drop it without penalty in accordance with Clause (i) above.

The ball may be cleaned when lifted under Rule 25-1b.

(Ball rolling to a position where there is interference by the condition from which relief was taken — see Rule 20-2c(v).)

Exception: A player may not take relief under this Rule if (a) it is clearly unreasonable for him to make a stroke because of interference by anything other than an abnormal ground condition or (b) interference by an abnormal ground condition would occur only through use of an unnecessarily abnormal stance, swing or direction of play.

Note 1: If a ball is in a water hazard (including a lateral water hazard), the player is not entitled to relief without penalty from interference by an abnormal ground condition. The player must play the ball as it lies (unless prohibited by Local Rule) or proceed under Rule 26-1.

Note 2: If a ball to be dropped or placed under this Rule is not immediately recoverable, another ball may be substituted.

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