Somewhere in a conversation about his arm — a doctor's visit, a guide you read at 11 p.m., a coach explaining why he's being held out — the phrase "growth plate" came up. Maybe it was explained. Maybe it was said quickly, in passing...

The morning after he pitches is when the arm tells you the most — if you know which questions to ask.

He woke up sore. You heard about it before breakfast — or saw it in how carefully he moved reaching for things, or in the stiff way...

He's always been the flexible one. Could touch his palms flat to the floor in third grade. Coaches love it — "great range of motion, throws so loose." And for a long time, the arm backed that up.

Then something started shifting. Not ...

Monday morning after a heavy weekend. You ask how the arm feels. He shrugs — "it just feels dead." Flat. Heavy. Doesn't have its usual life to it.

And you're standing there trying to figure out if that's what hard work feels like or ...

Somebody at the field mentioned it. Maybe it was a coach talking about another kid on the team. Maybe it was a parent. Maybe it was the moment your pitcher grabbed his inner elbow after a warmup pitch and you did a quick search and ...

You've been tracking your pitcher's development for years. Then comes the growth spurt — four inches in eight months, shoes that don't fit, sleeves that were long last season — and right in the middle of it, the arm starts sending signals i...