Keeping the left wrist in this flat position will allow the correct movement of the wrists at the top of the backswing, and the starting of the downswing, which is an up and down motion, keeping the clubface maintained in the proper position throughout the swing.
To check to see if the wrists are in the proper position that was mentioned above, swing the club half-way back about hip-level high with the clubshaft in the position horizontal to the ground. If the left wrist is in this flat position the clubface will be parallel to the target line, or the toe of the club will be pointing vertically towards the sky. Half-way through the forward swing with the shaft horizontal to the ground again the clubface should be parallel to your target line or toe facing upwards towards the sky. In these positions the left wrist has remained in the flat position throughout your entire swing which translates into a solid straight shot on line to your target. Finally, remember that any attempt to hit the ball with your hands will force the wrists out of position, and the cause them to break down which results in wayward shots.
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