Not all rookies are the same. And not all situations are the same at the point 'only allowing two runs.' His FIRST cup of coffee, in a game that could have very easily gone south, quickly, with someone who isn't projected to be like (put in any higher rated hopeful pitcher here), so pull him and hopefully preserve the game. He did okay his first couple innings, got a hit (yeah, I know, kind of funny, but still), he will take with him some good positives. Heck, that he was up at all, is something. I don't think there can ever be a standard 'allow so many innings' for all rookies to 'develop' or 'evaluate' (which isn't the time or place for anyway in this particular situation, imo.) He got his taste, he's got some things in his mind now (hopefully) of how to better approach things (if he can), that's the learning and development right there, no matter the length of the outing. It was enough. Onto the next game with momentum of a win rather than a deflating blow out.