What is up with Jonathan Papelbon? Granted relief pitchers are volatile, but a lot of that has to do with the smaller sample sizes they have compared to starters each year. Even looking at stats that are not as affected by the sample limits however, show a much different Papelbon in 2009.
In terms of pitch selection, Papelbon is throwing his slider more than he ever has and although it has improved in isolated results, the increase in usage might be in part because, and by no means offsets, the big drop in fastball effectiveness. From 2006 through 2008, Papelbon’s fastball was worth about three runs more than average per 100 fastballs. This year it is down to just 0.76. His velocity has not diminished though as far as obvious answers go.
In terms of location, Papelbon is hitting the strike zone at the worst rate of his career, down below 50% compared to the previous three year average of around 55%. Hitters are laying off pitches more than ever before as well, which is hurting both Papelbon’s strikeout and walk rates.
In terms of results, Papelbon is missing bats at almost half the rate that he did in his amazing 2007, and his 9.8% figure in 2009 is down from his three year average of 14.4%.
All in all, Papelbon has a 4.12 FIP and a 4.40 tRA, leaving him on pace to be worth just one win over replacement, a marked departure. His runs per inning pitched this year in just 30% what his 2006-8 value was.