Adam Wainwright, Run Clusterer
On Monday night, I was watching the Cardinals battle the Royals when I heard something that stopped me in my tracks. As Adam Wainwright labored in the sixth inning — two runs in and runners on the corners with two outs — the Cardinals announcers mentioned one of Wainwright’s greatest strengths — in their minds, at least. “That’s something that Adam Wainwright is really good at, is not compounding the inning… going back and getting the next guy.” I’ve been a Cardinals fan my whole life — and to that tidbit, I said, “Huh?”
It was, in truth, something I’d never thought about. Are some pitchers better than others at turning off the tap, amping up their performance when they need it and keeping crooked numbers from getting even crooked-er? My saber sense was tingling — something about this didn’t sound quite right. But of course, these spots are exactly where if a pitcher could bear down more than expected, it would make the most difference. I decided I’d try to find out how real this effect was.
Defining what I was looking for turned out to be a difficult. What, exactly, does “not compounding the inning” mean? The announcers seemed to think it meant that Wainwright pitched better after runs were in, or at least pitched the same while most pitchers in baseball got worse. Either way, the general idea was that his ones and twos turned into threes and fours less often than average.
One possible reaction to that might be “So?” His ERA is his ERA, regardless of whether it comes via a three-run spurt and eight zeros over nine innings, or three one-run frames and six zeros. To that I say: reasonable point. There are still reasons to care, though. For one, if a pitcher were actually prone to clustering, they’d tend to underperform their FIP over time. One of the reasons home runs are so bad is because they always result in runs, whereas other hits can be scattered around in otherwise dry innings without damage. A cluster-prone pitcher wouldn’t have that advantage; when you give up baserunners in bunches, a single and a home run become much closer in value.
In the same way, a pitcher who was prone to lots of singleton runs allowed but then mysteriously got better after letting one in would beat his FIP over a long time horizon. Base/out states tend to be more dangerous after a run has scored, naturally enough. Getting better then, or not getting worse while most pitchers do, would be quite the superpower. Read the rest of this entry »