In part sixteen of my almost 50 part series “Better Know An Oriole” (otherwise known as 2009 Orioles retrospective), I take a look at reliever Brian Bass… THE FIGHTIN’ UNUSUAL HOME RUN RATE!
Bass came over to the O’s at the end of the 2008 season, and took Lance Cormier’s long-man job going into 2009. Despite being 27 years old, he had only one year of experience in the majors under his belt. I projected him to pitch 45 innings with a 4.58 ERA in the pre-season.
Due to the lousy O’s rotation, Bass got much more work than I had expected. He ended up pitching 86.1 innings with a 4.90 ERA. He upped his strike-out rate from ’08, but at 5.63 K/9 it was still on the low side. Additionally, his walks jumped up to 4.59 BB/9. It’s hard to be effective that way, but Bass did get a ton of groundballs – his 61.4% GB rate was the highest in all of baseball amongst pitchers with at least 80 IP. Despite that, Bass still managed to give up a bunch of home runs. His 1.15 HR/9 was worse than average and was largely the result of a 16.2% HR/FB rate. It was 15.6% in 2008, so instead of moving back towards the mean it actually got worse. I don’t imagine there’s anything particular to Bass that would explain him giving up longballs that often (perhaps grooving a disproportionate number of pitches?), and adjusting for that moves his FIP down from a base value of 5.21 to an expected value of 4.63. Instead of being a below replacement level pitcher like he was this year (-0.3 WAR), Bass might have only been around a replacement level of bad.
Bass was able to get so many groundballs by throwing a low 90s fastball with a lot of sink to it – even more so than Brad Bergesen’s, and with more giddy-up to boot. He also threw a couple of breaking-balls; a slider with mediocre movement and a curveball with what looked like above average break both horizontally and vertically. The pitch values seem to back that up, with his slider being -1.49 runs relative to average (that is, below average) per 100 thrown vs. -0.31 for the curve. It was like that in 2008 too, with the slider at -0.69 and -0.58 for the hook. Bass went from throwing the slider more in ’08 (19.8% of the time to 9.7% of the time) to throwing the curve more this year (15.9% to 11.1%). It might not be a terrible idea to move a bit further next year.
I imagine Bass will be back in the O’s pen next year, and given his impressive groundball rate I think he could be an asset there. If he could maintain his strike-out rate while getting the walks down to their 2008 level (3.12 BB/9) and having his HR/FB rate normalize towards 11-12%, he could post an ERA closer to 4.25. That’s not great, but it would certainly be valuable to the team.