When must a match-play ruling request be made to be valid?

In match play, players may settle Rules issues by agreement, and the outcome stands even if wrong, as long as they didn't knowingly agree to ignore a Rule or penalty. If a referee is assigned to the match, the referee must rule on any issue that comes to their attention in time, and players must follow it (Rule 20.1b(1)).

A player may request a ruling, or, if no referee or Committee member is available in reasonable time, notify the opponent that a ruling will be sought later (Rule 20.1b(2)). To be considered:

• Facts known before either player starts the final hole: request before either player makes a stroke to begin another hole.
• Facts learned during or after the final hole: request before the result of the match is final.
• About an earlier hole: only if the opponent gave a wrong number of strokes or failed to tell of a penalty, the player didn't know the facts earlier, and the request is made in time.

Late requests get no ruling and the hole result stands. After the result is final, a ruling is given only if the opponent knowingly gave wrong information about strokes or penalties (Rule 20.1b(3)). Players can't play two balls in match play.