To clarify it was stroke play so the correct term would be competitor. I am asking because this happen to my daughter. She did not see the marker move and her competitor, stated something to the effect "I think you ball marker moved", "it move a little". Her comptetitor never showed her the direction the marker moved. So she could not know the original spot. Now to understand we are talking maybe no more then a 1/8 of an inch. At the scorers table it was brought up and my daughter was given a two stroke penalty, she states she could not tell that the marker moved. I am not sure about if there should be a penalty or not since the player had no visual klnowledge of the move and was not shown where the original spot was from her competitor. Also, I believe rule 1-4 in reference to equity of play the player that moved the marker should also have been given a one stroke penalty under decision 20-1/7, which addresses a caddie moving an apponents ball marker.. I am trying to make this a learning lesson for her so she learns how to deal with these situations as they happen on the course.