A look at the league leaders and trailers this year in homers per nine innings shows that's for good reason. The test was simply looking at the current rate and comparing it to that pitcher's rate from 2010-2012 (needed 300 innings pitched). While homers are not a pitching category in most leagues, they have a dramatic impact on ERA. Thus far this year (through Wednesday), there have been 2,909 runs scored on 1,852 homers – 1.57 runs per homer. We've isolated how these runs-scored-per-homer should be expected to contribute to each pitcher's ERA, too. League average this year is one homer per nine innings. So if you are half-a-homer-per-nine under, you should expect an ERA savings of a little more than three quarters of a run. Vice versa if you a half-a-homer over. Here are the current leaders in limiting jacks: Since the dawn of the sabermetric revolution, homers have always been put into the "pitcher's responsibility" column, along with walks and strikeouts.