Rules on the course
Backstopping, Helping Balls and Interfering Markers
A ball accidentally striking another is not the same as an agreement to leave a ball as a backstop. Resolve helping or interfering balls before the stroke.
Competitive Play · Updated October 22, 2026
The agreement is the fact that changes
Original worked comparison
The agreement is the fact that changesCASE 01
No arrangement
A ball remains on the green and another accidentally hits it.
Apply the collision provisions to the actual facts.
CASE 02
Agreed backstop
Both stroke-play players agree to leave the ball to help and the stroke is made.
Rule 15.3 a’s general-penalty provision applies to both.
CASE 03
Interference off green
A ball interferes with another player’s reasonable stroke.
Use the permitted lift, preserve the spot and obey cleaning limits.
CASE 04
Marker in the way
A marker helps or interferes.
Move and restore it under the applicable procedure.
Fictional cases and stated event assumptions. The exact official rule, eligible player category and actual Committee notice determine the real procedure.
The short version
- A helping ball on the green has a lifting procedure.
- An agreement to leave it to help in stroke play can penalize both players.
- An off-green interference lift does not automatically allow cleaning.
Resolve a helpful ball before playing
If a player reasonably believes a ball on the putting green could help play, the rule gives a way to have it lifted. Do not rely on a private agreement to leave it as protection against running past the hole.
In stroke play, an agreement to leave a helping ball followed by a stroke engages the rule even though nobody touches the moving ball. Deliberate positioning or deflection can also raise Rule 11 questions; an accidental-collision slogan cannot cover those actions.
Mark and return the right object
A lifted ball that must be replaced needs its original spot preserved. If a marker itself interferes, establish a reliable reference before moving it and restore the spot before the ball is played. Do not silently convert a marker move into a new ball position.
Off the putting green, a ball lifted because it interferes may not be cleaned under that permission. Keep the reason for lifting attached to the handling procedure.
Track the collision separately if it happens
Where the stroke began, what it struck and the form of play decide the collision outcome. Both balls on the putting green before a stroke-play collision is a particular penalty case, not the definition of backstopping.
Use the collision matrix for that stage and cleaning permissions before wiping a lifted ball.
Official sources
Official provisions checked October 22, 2026. Read their full wording and current event conditions.
Your next move
Read the governing source
Check the complete official procedure and your event conditions before acting.
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