With this play, your going to try and get the force out at third base. A good bunt will make it difficult for this play to succeed since there are only two players charging. If in doubt, get the out at first.
The key to the play is again the pitcher and shortstop working together to decrease the lead of the runner at second.
As the pitcher completes his stretch he will look back to second base, the shortstop will make a break toward second to get the runner to take a couple of steps back. If he doesn't move the shortstop should continue to second and the pitcher should step off or attempt a pickoff at second. This play can be used as a daylight play if the runner doesn't move back towards second base. The shortstop can be more agressive in driving the runner back since that's his main responsibility in this play. When the pitcher sees the runner move back towards second, he should deliver the pitch.
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Field any ball that is in front of you that you can get to before or at the same time as the pitcher or first baseman. You have an easier throw since your momentum is moving you towards the field. Chances are if you and any fielder are going to arrive at the bunted ball at the same time, then there will most likely only be a play at first base. Remember, you are in charge of where the ball is to be thrown. The goal is to try and get the out at third, but on a ball that is bunted well, you may have to call for the ball to go to first.
You will break towards home early as the pitcher is completing his stretch. The idea is to make the hitter think that the third baseman is coming in hard. As the pitcher delivers the pitch to the plate, the third baseman will stop and start backing up towards third. He can't run straight to third because he will still have to field any ball that is bunted hard enough that the pitcher can't get to it. Once the ball is bunted, he will get back to cover third base.
Pitcher will charge on the third base side of the infield. That half is his responsibility.
In this situation, position yourself as if you're holding the runner at first. As the pitcher takes his stretch, start creeping in toward home and break as he starts his delivery. Since the pitcher is covering the third base side of the infield, you will need to cover from the foul line to the mound.
You will be covering first on the play.
Described above. Covering second base.
Back up third base.
Back up second base.
Back up first base.