You often hear pitchers, managers and pitching coaches talk about hitting the corners and avoiding the middle of the plate for sustained success in the big leagues. One of the big stories out of Mets camp this spring was that Matt Harvey was "corner, corner corner" in his bullpen sessions, which was encouraging for his command post Tommy John surgery. Kirk Nieuwenhuis said of Harvey,
"I stood in on his last bullpen here when he was throwing and he missed maybe one pitch over the middle of the plate. I think he threw 25 fastballs and it was just corner, corner, corner. I think people forget a little bit how good he was.’’
Big leaguers talk about how the best pitch in baseball is a well located fastball. Ryan Zimmerman said,
A well-located fastball is still the hardest pitch to hit in the big leagues. I think some people forget that sometimes.
It's especially important for finesse pitchers, like a Dillon Gee or a Mark Buehrle, to live on the corners to have consistent success in the big leagues with a non swing and miss repertoire. That kind of stuff was hard to quantify without watching every pitch of every at bat, but yesterday, new public data became available that will help guide us in that direction.
Bill Petti created a statistic a few years ago called Edge%, and it's one of my favorite statistics that fantasy owners probably haven't heard of yet. Edge% shows how often a pitcher hits the edges, or corners, of the strike zone. Petti has hypothesized that higher percentages of pitches located on the edges of the plate lead to a lower ERA, FIP and BABIP for pitchers. It's another great tool to put in the toolbox for our player evaluation. The database for Edge% is located here.
Heart%, also located in the database, is another very useful tool. It measures how often a pitcher misses over the heart of the plate. I have suspected that pitchers who miss over the heart of the plate more often will be more likely to have a higher HR/FB ratio, because pitches down the pipe are easier to square up and hit hard than pitches on the corners. I can't say this as fact, but it's an unconfirmed opinion of mine. Petti's data can help prove or disprove that theory, and it could lead to some changes in how we view xFIP.