Work on fielding the ball and coming up into throwing position. Work on drop steps right and left and SPRINTING back to get behind ball and then coming forward into throw with momentum. Easy to do with small spaces.
Work on drop steps and adjustments. Make this a quick drill with the coach tossing next ball as soon as player has caught previous.
This is a guide to each position's responsibilities. Everyone moves on every play. Baseball is a game of movement. Ball- field the ball if it's hit your way Base- Make sure you cover the base of your responsibility. Back Up- Every throw needs a back up from someone.
In the basement, it's real easy to work on this skill. Isolate the glove work on your knees or work on it from an athletic fielding position. "Work through the ball" with the glove in a controlled fashion. Another way to think is the "thumb goes through the ball."