His age...I just wouldn't rush him.
Blanton had a 2.57 ERA with 144 K and 19 BB in 133 IP in A.
1.26 ERA with 30 K and 7 BB in 35 2/3 IP in AA.
Greinke had a 1.14 ERA with 78 K and 13 BB in 87 IP in A.
3.23 ERA with 34 K and 5 BB in 53 IP in AA.
The curious thing about Greinke, is that he's so darned effective, even though his K numbers are not impressive at all. He's a control guy, I'd see him as a better Maddux.
Most top prospects do not spend much time in AAA. AAA is mostly for guys that are going to be minor leaguers for life, platoon players in the MLB, or guys they just can't find roster space for. With 53 innings in AA, I think they'll give Greinke a good amount of time there this year, but that's just my opinion. Another thing, is that Blanton has actually pitched competitively before. He was drafted out of college, Greinke out of HS. College pitchers tend to be on a faster track into the pros, because they are further developed. I agree that Greinke is a special case, but still...
Umm, disregard what I said earlier...I just read this link...
http://mlb.mlb.com/NASApp/mlb/mlb/news/ ... &fext=.jsp
Wow, I certainly did not expect that. So Greinke's going to start the year at AAA. They're happy with the 53 innings he did at AA, apparently. It's a decision that surprises me to say the least...a 20 year old at AAA is very uncommon. I would've given him some more seasoning at AA, since a LOT of top prospects are currently there. I personally think the guys he'd have to face there would do him good. What do I know, though...I'm not a baseball GM.
Anyway, since he's at AAA now, unless he doesn't do well, he'll get a callup soon. Like I said, top prospects usually don't spend too much time at AAA.