Sinkers and changeups
By: Single LThe sinker I recommend is a two-seam fastball, and it is thrown with exactly the same arm action, release point, and followthrough as the fastball. Some pitchers get good sinking action with the normal two-seam grip. Others move one finger in a bit toward the middle and off the seam, like a cutter. Depending on your mechanics, this can create a bit more movement, but it will also reduce velocity some. Start with the two-seam grip and experiment. The purpose of the sinker is to get ground balls. Throw it low, knees to mid-thigh, and hard. Even if you only get a few inches of downward movement, this will cause many ground balls.
Some sinker-ball pitchers try to get down-and-in movement by slightly pronating the hand at release. This means turning the palm slightly outward. Some pitchers do this naturally, as part of their fastball release. If you're one of them, fine. But don't force it. Over-pronating is risky for the arm.
There are probably a dozen or more grips for the changeup, and which is easiest depends on your mechanics and style. Many people think the circle change is hard to learn (and it does take time), but I think once you get comfortable with it you can get good, reliable results. Holding the ball off center creates a spin that yields late movement and helps kill speed. Experiment with the circle change and a straight change. The straight change is usually thrown with the ball "choked" back near the palm (usually not actually touching the palm, but close), so that there's a lot of finger area in contact with the ball. Throw it hard, like a fastball, and let the grip kill the speed. This may be easier for you to learn and to control, but it may be harder to get as much movement or kill as much speed, compared to the circle change.
No, don't pull your arm straight down with the changeup. Throw it exactly the same as the fastball. This is the secret to the deception. And don't slow your delivery or armspeed, because you'll tip off the hitters.
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