marking the ball

Question
Hi:
On the green, player A putts and strikes player B's ball which wasn't marked. Who gets the penalty?

Answer
Dear Rhea, Happy Holidays and thanks for the question.  This answer is dependent on whether you are playing match play or stroke play.  In match play, there is no penalty for either player. The ball that was at rest must be replaced, while the ball that was putted, must be played as it lies.  In stroke play, the player who putted and struck the other player's ball would incur a 2-stroke penalty.  Once again the ball at rest has to be replaced to its original position.  In both match play and stroke play, the player with the ball at rest never incurs the penalty.  Happy New Year, Good luck, thanks again and remember...

Love the game
skipper