The differences between good J.A. Happ and bad J.A. Happ can be so subtle in their cause yet so drastic in their manifestation.

In grabbing the attention of the baseball world in 2009 and keying the return package for Roy Oswalt in 2010, Happ was tremendous. In getting himself sent to the minors in 2011, he was the opposite of tremendous.

His stuff was the same — really. And his 2010 and 2011 numbers featured nearly identical walk rates (4.8 per nine innings both years) and strikeout rates (7.2 per nine innings in 2010 and 7.7 per nine innings in 2011).

But the results were nothing alike. His ERA soared from 3.40 in 2010 to 5.35 the next year, with only a three-week stint in Class AAA keeping him from qualifying for leader boards that would have him near the bottom.