To be a fantastic putter requires consistency and accuracy.
Both of these factors depend on the putting stroke of the golfer to be incredibly simple. The less movement in the putting stroke, the less movement that there is to control or that can go wrong.
A simple putting stroke is one that is generated from the shoulders which are the big muscles that should be used for a pendulum style motion. Everything else should stay very still, particularly the smaller muscle groups such as the wrists and arms. Any movement that occurs in these smaller muscles causes bending at the elbow or wrist joints, and turns a smooth putting action into a jerky, flicking action. This makes it difficult for the golfer to perform the same movement for every putt and control the club face through impact to hit the putt accurately.
To control any bending in the wrists in the putting motion, focus on these two points:
Grip
Make sure that your putting grip is symmetrical, where the two hands work together as one unit.
To achieve this, check that the two thumbs point straight down the flat front of the putter grip and that the palms of the hands face each other down each side of the putter grip. If this is achieved the two hands can work together rather than fight each other and any bending of the wrists can be minimized.
Arm/wrist position
The putter should be held so that the arms and the putter create a letter 'Y' in shape.
This position should be maintained throughout the entire putting swing. In essence, the arms and wrists do not move and the shoulders swing the 'Y' shape backwards and forwards. You should be able to see the 'Y' shape clearly at the set up, the end of the back swing and the end of the forward swing.
Practise
To practise keeping the wrists still, take a spare golf ball and set up to a putt as normal except that you should hold the putter three inches lower down the grip than normal.
Now take that spare golf ball and position it so that it is held in place in-between the left wrist crease (for right handed golfers) and the putter grip.
When you hit your putt, if you keep the wrists still, the ball will stay in position, however, if you move your wrists or arms the ball will be dislodged and fall to the floor.
This is an easy way to check for unwanted wrist movement in a putting swing.
Use this information and practice drill to control any wrist bend in your putting stroke and improve your putting.