Watson: Changing breaking balls, by movement

From SABR member Owen Watson at FanGraphs on May 6, 2015:

Yesterday, we looked at the biggest changes in fastball movement (rise and sink) in starters and relievers from their offerings in 2014 vs. this season. Today, we’re going to do the same thing with breaking balls (pitches known for their movement), which should hopefully yield some interesting takeaways as we move forward with this young season.

As I said in the previous article, more movement doesn’t always mean better results: it can be a catalyst for some changes in peripheral numbers, however, and can point toward raw improvement in a pitch. We’ll go into some information related to whiff rates and batted ball profiles with these breaking pitches, looking for any change in production that goes along with change in movement.

The standard preface: all stats are farmed from Baseball Prospectus’ PITCHf/x leaderboards. It’s obviously still very early, so take these results with a grain of salt, and mostly as something interesting to watch as the season progresses. Today we’ll divide these pitches by curveball and slider, looking at starters and relievers together. We’ll also divide sliders by lefties and righties, as the movement data is obviously quite different for each of them. As a baseline, I’ve used a 50 pitch minimum for both starters and relievers in 2014.

Read the full article here: http://www.fangraphs.com/blogs/changing-breaking-balls-by-movement/

Originally published: May 6, 2015. Last Updated: May 6, 2015.