If the cue ball is anywhere within the shaded area, a shot at the 8 ball in the side can result in a common scratch. Although the natural tangent line is to the short rail clear of the corner pocket, many beginners end up scratching in the corner (broken blue line). This is because the cue ball picks up natural forward due to table friction. Forward will cause the cue ball to bend off the tangent toward the corner pocket. Remember, to follow a natural tangent line there can be no roll or spin on the cue ball when it contacts the object ball.
Protect yourself against the scratch in this situation by placing a little bottom on the cue ball. When the cue hits the object ball it will bend the tangent line back away from the corner.
IMPORTANT: Do not shoot easy believing you can pull the cueball up short of the corner! If you are too timid, the cloth will rub the bottom spin off the cue ball causing it to start rolling forward. The cut is too thin to shoot easy and expect the cue ball to consistently stop short of the corner.
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