A basic way infielders can adjust to the ball to get a short or long hop is by moving their feet. Proper footwork is essential for getting the hop you want.
For this discussion, assume the fielder is right-handed (lefties should do the reverse).
APPROACHING THE BALL
For a routine ground ball (a ball that the fielder can easily get in front of), you should approach the ball a little on the right side. A good cue is to line up your left shoulder with the ball. There are three advantages to this approach: (1) the slightly offset view helps you see the hops better, (2) you are in a better position to catch the ball on the left side of your bellybutton (more on this in 3. Glove Presentation), and (3) it gives you momentum towards first base. Below are a couple videos, one short and the other longer, explaining the approach.
RIGHT FOOT, LEFT FOOT, CATCH
Beat the ball to the spot with your right foot. The goal of the infielder as he approaches the ball is to beat the ball to the spot where you want to catch it. You beat the ball to the spot with your right foot by planting it on the right side of the ball. After you beat the baseball to the spot with your right foot, you adjust and time the catch with your left foot.
Adjust to the ball with your left foot. After planting your right foot, adjust to the ball with your left foot. Where you place your left foot allows you to catch the short hop, push through the in-between short hop, or drop step for a long hop. Many instructors teach to place the left foot slightly in front of the right foot to create momentum towards first. However, there is an argument for keeping the left foot slightly behind the right foot because it increases adjustability (click here for more information). Regardless, the goal is to place the left foot in a way that makes it possible to catch the short or long hop.
Time the catch with your left foot. As you move to your left foot, time it so that the left foot lands on the ground in rhythm with the glove catching the ball.
Keep your feet moving. Keep your feet moving as you prepare to catch the ball. The movement does not have to be fast or quick. It can be a slight movement that is slow and controlled. The important thing is not to let the feet come to a stand still. Once that happens it is more difficult to get your body moving again.
BACKHAND AND FOREHAND
The right foot, left foot, catch sequence not only applies to balls hit directly at the infielder, but also with routine backhands and forehands. If possible, the right foot should beat the ball to the spot where you want to catch it. Then the left foot will adjust to the ball to get the short or long hop. The left foot should land in rhythm with the ball hitting the glove. Note, however, the basic right foot, left foot, catch sequence may not work on more difficult backhands and forehands. In these cases, the footwork you should use will be dictated by the situation.
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