Normally you will call this play when you have a catcher that is capable of throwing out the runner stealing second and that potential run is more critical than the runner at third, meaning it's late in the game and you're up by 2 or more runs. If you have a catcher that lacks arm strength, then this play may end up with a runner at second and a run scored.
When throwing through to second, your first goal is to try and get the runner stealing second. If the runner at third breaks for home, it's up to the second baseman to let the shortstop know that he is going home. But, if the out is more important than the run, the shortstop should get the out at second and let the run score.
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As you come up to throw to second, you must pick up the runner at third. The general rule is, if you see his shoulders squared towards you, you throw to third. If he's not coming then make a good throw to second.
You have to be ready for the snap throw from the catcher. Make sure the ball isn't hit and then quickly cover your bag.
Same as on any steal, except there may be a return throw from the shortstop, so make sure you stay out of the way. You must be prepared to get involved in a rundown between first and second or home and third.
You must first hold the runner on first and then break towards home as the pitch is delivered.
You're responsibility is to watch the runner at third and let the shortstop know if he goes for home.
You will be covering second base. Don't worry about the runner at third. Listen for your second baseman to tell you if he's going. If you don't hear anything focus on receiving the ball and making the tag. Occassionally, the runner may stop and get in a rundown. His purpose is to keep a rundown going so the runner can score from third. It's essential that you run as fast as you can at the runner and make him go back towards first hard. This will force the runner at third to make a quick decision. Your goal should be to run the runner back to first and either tag him or make one throw to the first baseman for the out. Listen for the second baseman to tell you if the runner is breaking for home.
Back up third base.
Back up second base.
Back up first base.