Relay and Trail Man
The infielder who goes out to take the throw from the outfield on a deep ball.
How it actually works. The relay man is the deep one who takes the outfielder's throw and turns it round. The trail man is fifteen or twenty feet behind him, and he has two jobs: catch anything that gets past, and tell the relay man where to throw, because the relay man has his back to the play while the ball is in the air.
Why it is done, and when it is wrong. Whoever is not catching the ball is doing the talking. That is a rule you can apply to any play on any field, and it is why the trail position exists at all: you cannot look a throw into your glove and read the runners at the same time.
At Little League and travel ball. Coaches call it the trail position or the second cutoff. On a 60/90 field a ball in the gap is too far for one throw, so this is not optional the way it looks on a diagram.
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