One of the best weapons of a pitcher is strikeout. In theory, when you strikeout, you keep all the runners in the bases they are in. In some situations, however, a catcher needs to throw the ball after a strikeout. Some of these releases are routine, but others are crucial to the game.
Last ball of third strike
If you are the catcher, and either you do not catch the ball on the third strike or release it, the batter becomes a base runner and can run to first base. Then you need to throw the ball to first base to complete the out: otherwise, the batter is safe at first. However, if the first base is already occupied and there are less than two outs, there is no need to throw at first base since the runner is out.
Base Theft Attempt
Another crucial situation in which you might have to throw the ball after the strikeout is if the runner tries to steal second base. As a catcher, you should try to throw the base runner out to avoid stealing. When a catcher pulls a runner who tries to steal the base after a strikeout from the batter, it is commonly known as a double play "strike 'em out, throw' em out".
Around the frame
If a strikeout occurs and there is no one in the bases, it is common to see that the catcher will throw the ball either to the first or third base. This initiates the throwing of the ball by all the equipment by all the field, which is known like "Around the horn" or around the picture. The ball will often go to the player at third base, second, shortstop, after returning to the player at third base. Sometimes, the ball goes from first base to shortstop, second base and third base. Almost always, when you see a team go "around the horn", the man at third base receives the ball last before returning the ball to the pitcher. This is usually done to keep the players warm and ready in case the next batter directs the ball to them.
Pitching back to pitcher
"Around the horn" only happens when there are no runners on base, as there is always the risk that someone will not catch the ball and a runner will steal a base. When there are runners on base after a pitcher eliminates a batter, the catcher throws the ball back to the pitcher. Although this is a routine release, it is very important: pitching the pitcher badly can result in a runner stealing a base.