A player may replace a ball by following a rule or rules that allow the player to play, drop or lay down another ball to complete the hole. The replaced ball becomes the ball in play.
If a player replaces a ball and is not permitted to do so under the rules, the replaced ball is not a fault ball; it becomes a ball in play. If the error is not corrected as provided in Rule 20-6 and the player takes a stroke after the incorrectly replaced ball, he loses the hole in stroke play or incurs a penalty of two strokes in stroke play under the applicable rule and must finish the hole in stroke play with the replaced ball.
Exception: If a player incurs a penalty for playing a stroke from the wrong place, no additional penalty is incurred for the unauthorized replacement of a ball. (Ball played from the wrong place - see Rule 20-7.)
Status: 2018