Rules of Golf - Rule 19: Ball in Motion Deflected or Stopped

Spectators take cover as a wayward shot heads into the crowd during The Travelers Championship
Golf spectators ducking and covering? Never a good sign. Tim Clayton/Corbis via Getty Images

The Official Rules of Golf appear on the About.com Golf site courtesy of the USGA, are used with permission, and may not be reprinted without the permission of the USGA.

19-1. By Outside Agency
If a player’s ball in motion is accidentally deflected or stopped by any outside agency, it is a rub of the green, there is no penalty and the ball must be played as it lies, except:

a. If a player’s ball in motion after a stroke other than on the putting green comes to rest in or on any moving or animate outside agency, the ball must through the green or in a hazard be dropped, or on the putting green be placed, as near as possible to the spot directly under the place where the ball came to rest in or on the outside agency, but not nearer the hole, and
b. If a player’s ball in motion after a stroke on the putting green is deflected or stopped by, or comes to rest in or on, any moving or animate outside agency, except a worm, insect or the like, the stroke is canceled. The ball must be replaced and replayed.

If the ball is not immediately recoverable, another ball may be substituted.

Exception: Ball striking person attending or holding up flagstick or anything carried by him – see Rule 17-3b.

Note: If a player’s ball in motion has been deliberately deflected or stopped by an outside agency:

(a) after a stroke from anywhere other than on the putting green, the spot where the ball would have come to rest must be estimated. If that spot is:
(i) through the green or in a hazard, the ball must be dropped as near as possible to that spot;
(ii) out of bounds, the player must proceed under Rule 27-1; or
(iii) on the putting green, the ball must be placed on that spot.

(b) after a stroke on the putting green, the stroke is canceled. The ball must be replaced and replayed.

If the outside agency is a fellow-competitor or his caddie, Rule 1-2 applies to the fellow-competitor.

(Player’s ball deflected or stopped by another ball – see Rule 19-5)

19-2. By Player, Partner, Caddie or Equipment
If a player’s ball is accidentally deflected or stopped by himself, his partner or either of their caddies or equipment, the player incurs a penalty of one stroke. The ball must be played as it lies, except when it comes to rest in or on the player’s, his partner’s or either of their caddies’ clothes or equipment, in which case the ball must through the green or in a hazard be dropped, or on the putting green be placed, as near as possible to the spot directly under the place where the ball came to rest in or on the article, but not nearer the hole.

Exceptions:
1. Ball striking person attending or holding up flagstick or anything carried by him – see Rule 17-3b.
2. Dropped ball – see Rule 20-2a.

(Ball purposely deflected or stopped by player, partner or caddie – see Rule 1-2)

19-3. By Opponent, Caddie or Equipment in Match Play

Exception: Ball striking person attending or holding up flagstick or anything carried by him – see Rule 17-3b.

(Ball purposely deflected or stopped by opponent or caddie – see Rule 1-2)

19-4. By Fellow-Competitor, Caddie or Equipment in Stroke Play
See Rule 19-1 regarding ball deflected by outside agency.

Exception: Ball striking person attending or holding up flagstick or anything carried by him – see Rule 17-3b.

19-5. By Another Ball
• a. At Rest
If a player’s ball in motion after a stroke is deflected or stopped by a ball in play and at rest, the player must play his ball as it lies. In match play, there is no penalty. In stroke play, there is no penalty, unless both balls lay on the putting green prior to the stroke, in which case the player incurs a penalty of two strokes.

• b. In Motion
If a player’s ball in motion after a stroke other than on the putting green is deflected or stopped by another ball in motion after a stroke, the player must play his ball as it lies, without penalty.

If a player’s ball in motion after a stroke on the putting green is deflected or stopped by another ball in motion after a stroke, the player’s stroke is canceled. The ball must be replaced and replayed, without penalty.

Note: Nothing in this Rule overrides the provisions of Rule 10-1 (Order of Play in Match Play) or Rule 16-1f (Making Stroke While Another Ball in Motion).

PENALTY FOR BREACH OF RULE:
Match play – Loss of hole; Stroke play – Two strokes.

©USGA, used with permission