Leaning forward in your slide causes an abrubt, short slide. An abrubt slide reduces the efficiency of energy transfer to the ball and causes aiming problems.
The first and easiest thing to check is ball weight. Make sure that your ball is not too heavy to control confortably
Monitor your approach for the loss of synchronization which is causing your swing (and the ball) to be ahead or behind your stride. The problem will very likely be found in your pushaway and first step. You may also be "muscling" the ball during the forward part of your swing, causing your swing to move ahead of your stride
Stand erect throughout your approach and slide. At no time should you allow your body to bend forward. As your weight comes forward from your right foot into your last step, stride down into your sliding stance and begin sliding on the ball of your left foot. As you slow to a stop, all of your weight should be centered over your left foot.
Hold the slide stance pose with your weight over your left foot until your arm
follow-through is completed.
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