The Situation: Runner on third, one out, tie game, bottom of the 8th. The runner on third knows that all of the outfielders have above-average arms.
The Play: The batter hits a hard fly ball down the left field line, to medium left field. The runner sprints back to the bag, facing the mound, ready to tag up. He watches as the left fielder sprints over towards the line. As the left fielder gets towards the line, the runner has to turn his body more and more, looking back almost behind him over his left shoulder so that he can see the outfielder. The outfielder makes the catch and the runner quickly turns and takes off for the plate.
The Outcome: The outfielder makes a strong throw and the runner is out by a half a step. The game remains tied.
What Went Wrong?
The base runner was right to tag up in that situation. With a medium fly ball into the outfield, you have to force the defense to make the play. But the runner was not mentally prepared to tag up. It seems strange that tagging up requires thinking, but it absolutely does. The moment the ball is hit down the line, the runner has to give himself the best view of the ball so that he can leave right when the outfielder makes the catch. That means that the runner has to turn so that his body is facing foul ground, towards the third base coach’s box. By doing this, the runner cuts out the turn that he needed to get going towards home. This could be the difference between safe and out. Thinking through the details extends to running the bases. Always be prepared and always think the game.