Putting is difficult. A combination of reading the perplexing undulations on the greens and maintaining a smooth and consistent stroke is a tough combination to consistently produce.
As such, we all look for ways to make putting a little easier. We might invest in a zero-torque mallet putter. We might draw a straight line on our ball, we might even go so far as to try the AimPoint method of aligning oneself on the greens.
All those things are legal, so long as you don’t take too long to do them. In top-level competition you might fall foul of pace of play policy if your pre-shot-putting routine is too lengthy.
But there are some things one cannot do on the putting green to make things easier. You can’t leave the flagstick lying on the ground behind the hole to act as a backstop. You can’t have a practice putt on another bit of the green before you play to get an idea of the pace. And…
You can’t put a marker down ahead of your ball to indicate the intended line of your putt and help you aim.
If your opponent places a coin down ahead of their ball to help with their aim and line, they are breaking the Rules.
In fact, they’re breaking Rule 10.2b. Section 3 of that Rule says that you must not set an object down to help with aiming.
A coin placed ahead of the ball is an object set down to help with aiming – You cannot avoid a penalty if you have done this – even if you remove it before making a stroke.
Your opponent had broken Rule 10.2b(3) and should have faced the general penalty of two strokes in stroke play, or in this case, in match play – it would be loss of hole.
There is nothing to stop you using a natural feature of the green to help you with your line. Say there is a darker patch of grass that is a good target for the first part of your putt, you can aim at that.
If a leaf has blown onto the green and it’s a good target, you can aim at that. But you can’t go and place a leaf on your target line. Rule 8.1a(2) states that you cannot move a loose impediment into a position to improve the line of play.
Basically, you cannot deliberately put something on your line, a coin, a marker or even a loose impediment, to help with your aim and line. Your opponent was in the wrong and should have been penalised.
