When you have a kid like Starling, I think High A is fine for his first year, what would be his freshmen year, and you give him a number of goals for the year, all attainable.
You have him become a centerfielder everyday, and he plays every game. You get him used to his new life and help him reach each goal.
He stays at High A no matter what all year (failure or success), and if he reaches his goals, then he plays next year at Double A, as the teams starting centerfielder. And then you do the same thing again. If he accomplishes all of these goals, then Triple A is available the following season.
It's good to give these kids a full season at each level. Getting used to seeing pitchers multiple times, focusing on specific goals rather than broad big picture goals. Have them learn the little things, grow and mature. Teach them the basics, the way of life etc. Full years in the minors at each level.
Now Starling has the talent that he could reach Triple A as early as 2013, but that's rather aggressive in my mind. But if he is really showing he can handle it, is mature enough by August of 2013 and has been knocking out each goal, it's possible. You also need to know if you send him there that failing won't hurt him. He needs to be able to learn from failing.
I think 2014 call up is possible, but then again, I don't know enough about the kid to really say any of this. I just know how his talent is rated. And the things I have heard make me think he might be a very unique talent that is a steal at 5th overall. He might be more productive as a big leaguer one day than Harper or Trout. Which is really saying something.
But let's see how he does this year. High A would be aggressive, but it sounds like a level he could do. Rookie ball is where most high school graduates go, hell many college graduates do too.
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