Succeeding with secondary pitches

This post does not concern the best secondary pitches; BtBS has already covered the best pitches in MLB. This post is about the best secondary pitches, when those pitches are compared to the primary pitch. Allow me to elaborate.

Let's establish some facts about pitchers. We've got pitch information going back to 2002. Over that span, 1,708 pitchers have thrown at least 100 innings in a season. Of them, 1,465 (85.8%) have thrown a majority of fastballs, and 1,677 (98.2%) have thrown a plurality of fastballs*. This probably confirms what you already knew—pitchers rely heavily on fastballs.

There are still other pitches. Indeed, of the 1,708-man sample, the average fastball rate was 59.1% — more than four out of every ten pitches wasn't a heater. Sliders, cutters, curveballs, changeups, splitters — all of them are important and all of them compliment the main pitch: the fastball. But what about those pitchers who excel with one of these lesser pitches, but struggle with the fastball?

This is where it gets fun. See, FanGraphs has pitch type linear weights. In a nutshell, every pitch is given a run expectancy per pitch; you can view the aggregate values for any particular pitch on the leaderboards. As is noted on the FanGraphs page for the linear weights, these stats aren't particularly predictive — they'll tell you how well the pitch did, but not how well the pitch is going to do. Regardless, it's still interesting, at least for me.

What I wanted to do was compare each of the secondary pitches to the fastball; since these are raw totals, though, that would be difficult, as the fastball dwarfs them in usage. Luckily, FanGraphs also provides a rate stat (putting each value on a per-100-pitch scale), which would allow for a much easier comparison.

Now, as with all rate statistics, we need to be wary of small sample sizes. While setting minimum innings pitched at 100, I still needed to set a threshold for pitch usage. I settled at 10%, a bar that should ensure at least 100 of the pitch in a season.

After this, I brought my 1,708 pitchers into a spreadsheet and found the differences between their fastballs and their other pitches. Being the creative person that I am, I dubbed the new stat "[Secondary Pitch]-FB Diff". I then sorted them by the highest differentials; the top 10 results for each are below.

The top 10 tables for: sliders...

...cutters...

...curveballs...

...changeups...

...and splitters.

That's all I've got, at least for the time being. Now that I've fallen down the pitch type linear weights rabbit-hole, though, I'll probably investigate this further at some point in the future.

*In case you'd like to know, here's a chart with the plurality pitch usages and the pitchers who used them:

. . .

All statistics courtesy of FanGraphs.

Ryan Romano writes for Beyond the Box Score, the FanGraphs Community blog, and Camden Chat that one time. Follow him on Twitter at @triple_r_ if you enjoy angry tweets about Maryland sports and live tweeting about Community, Thursdays at 8/7c on NBC. Cool. Coolcoolcool.