During Saturday's Pirates/Cardinals game, Pirates' catcher Chris Stewart showed why it is so important to make sure to commit to your decision behind the plate.
Catchers, you must trust your first instinct and commit to a block if that is what you brain is telling you to do.
You could make the argument that Fransico Liriano threw a pretty filthy pitch here and that Stewart had little chance to block it. But, you'd be wrong. The moment Stewart's hands started to the ground, he should have initiated an all-out block to the ground. By leaving his chest and left knee up, he gave the ball room to squirt between his arms/legs and it lead to Cardinals' outfielder Brandon Moss scoring from 3B.
Something to keep in mind...As catchers, we often feel a lot of pressure when there is a runner on 3B. However, of all the situations, it is the one scenario where we actually have more room for error. Think about it, with a runner on 1B a ball that gets anymore than 3 feet away from us is likely to lead to the runner advancing to 2B. Same with a runner on 2B. However, with a runner at 3B, the ball has to actually get by us entirely in order for a runner to justify coming home. The ball could be 10 feet in front of us and the chance that a runner would have enough confidence to try and score is very slim.
This is why it is so important to remember. When in doubt - Block it out. It you think there's even a small chance a ball might head to the ground. Fire a FULL block. The worst thing that could happen is that you get smacked in the chest protector, or body, by the ball. Something that was going to happen anyway if the ball actually hit the ground. We might as well make whatever effort we give on a pitch like this actually count.
Don't second guess yourself, and don't fire a half block. Commit as soon as you start moving and always take the safe approach.