When scouting out the potential pitchers for your fantasy team, we typically glance at ERA first and foremost to get a sense of whether they pitched well the previous year or not. This is a mistake however as a pitcher's high or low ERA does not tell the full story. Whether a pitcher allows a run or not can be affected by so many things. As touched upon in my How To Evaluate Pitcher ERA article, we have a few tools at our disposal to really determine whether each pitcher's actual ERA was legit or whether luck played a factor in it.
In this article, I'm looking at the biggest differences between a pitcher's 2011 ERA and their xFIP or SIERA, which are two ERA predictor stats. In this first chart below, we have a list of 14 pitchers who seemed to have an ERA that was a lot better than it should have been last year:
Now, on the other side of the coin, let's look at the pitchers who had an ERA that was overly inflated which should improve in 2012:
As you can see, high BABIP combined with high HR/FB rates were the culprit behind most of these spikes in ERA. Those two stats are mostly out of the pitcher's control and usually will regress closer to league average rates the next season.