Commenting gone awry: A short lesson in Jake Peavy's walk percentage

It began as a simple comment. I thought I could do some baseball-type typing for a change and show that Jake Peavy, when pitching from the stretch (i.e. with men on base) was losing control, as shown by an increase in walks. The comment was well-received, but it wasn't as accurate or in-depth as it should have been. There was no average to compare to, the sample sizes were problematic, and I had forgotten to subtract intentional walks from my numbers. Being somewhat obsessive, I spent some time trying to make it right.

For this comparison, I chose a handful similar-type pitchers, i.e. righties with a large enough sample (this is all non-scientific, of course, and may still be dripping with problems) that have high K% (>20%) and below-average BB% (<8% for the most part). Oh, and Gavin Floyd for relatability. We could look at more pitchers. We could look at other types of pitchers. We could look at pitch selection and location. But we won't; I'm plowing ahead. Pitching from the stretch is another huge tub of owls that I don't intend on opening at the moment. This is only a revised attempt (IBBs for all pitchers were removed) to look at what happens to Peavy's BB% with runners on base. Because strike outs matter somewhat critically in men-on-base situations(plus they're the sister component for FIP), I looked at those trends, too. For simplicity, I'm only posting the walk numbers; the names link to each pitchers' Fangraphs splits page for 2011 if you don't trust my descriptions.

In this sample, Justin Verlander's K% has stayed fairly constant while his BB% has risen with runners on. The exception is last year, when his K% really spiked with runners on, approaching 30%. Recently he's getting the necessary strike outs, but the unintentional walks have risen, too. In earlier years, the K% was a bit lower, but so were the walks.

Josh Beckett's K% remains remarkably consistent with or without runners on the sacks, the exception being 2011 when it shot up about 6 points to 28.6% with RISP. His constant increase in walks are the most troublesome of this group.

Tim Lincecum was a rookie in 2007, and so pitched only 146 innings. Starting in 2008, his K% soared and remained consistently high no matter the base situation. As you can see, his walks are actually tending to decrease under pressure. That's some dominant pitching.

Javier Vazquez is interesting. His BB% remained surprisingly similar across the board, yet his K% tended to dip just a bit with men on. His biggest jump in walk rate, in 2011, came with a noticeable decrease in strike outs. Perhaps that's not a good sign.

We know Gavin Floyd. 2007 is a small sample, and, while generally trending upward when in trouble, his walk rates don't skyrocket. His K rates stayed within a few points, by and large. Little up, little down, no trends to speak of year-to-year. One thing I did notice, in 2008 and 2011, was that his HR/9 basically doubled with RISP. (Home runs being the other factor in FIP, of course). Very small sample size, but giving up more multi-run long-balls is something that fans watching at home tend to notice.

Now Peavy. I included ‘04 to ‘06 for a larger sample. For the most part his strike outs dipped with runners on, though they rose to very good heights in the same situation in 2008 and 2009. Recently, the Glass Bulldog's dramatic rise in BB% when concerned about runners looks troublesome. However, that's hard to take too seriously considering the partial seasons and his coping with injuries, not to mention a 5.9% walk rate still being pretty good.

What did I learn? First, intentional walks matter to an extent. Elite pitchers aren't often asked to pitch around anyone. Secondly, an increase in walks is often accompanied by an increase in strike outs when guys are on base. I take that to mean that good pitchers, when in trouble, will challenge hitters. If they fall behind, though, they'll back off; a walk is better than a hit in these situations, remember. Pure speculation on my part, though. Concerning Peavy, his rise in BB% over his career (the part catalogued here, at least) wasn't as drastic compared to some other good and elite pitchers as I originally thought. Whether an increase in walks is due to purported loss of control inherent to pitching from the stretch, nibbling around the plate, or simply added mental stress, that's not for me to say. Like I said, that's a whole other satchel of lambs. Whatever the culprit, though, it should probably be accepted league-wide to some degree (hint: not likely mental stress). We can remember this as a vague generality by quoting Bill Murray in Ghostbusters, when asked where the walks go: "They go up."

Also, as became clear to me, high BB% w/RISP isn't the end times; as you can see, Verlander basically doubled his walk rate the past two years when dealing with runners on second and/or third. I'm thinking that speaks to his command; if he's confident that he can paint the corners, he'll do it. His results during those years have been, well... alright. I guess.