Entering Tuesday’s start against the Chicago White Sox, a lot of Edwin Jackson‘s numbers stand out.
Naturally, to the untrained eye, a 5.24 ERA is the first red flag. But since ERA is a completely imperfect measurement of a pitcher, there has to be something behind Jackson’s inauspicious start with the Chicago Cubs.
In terms of Fielding Independent Pitching (FIP), Jackson has actually been a better pitcher than 2013 and projects to finish that way. Yet, Jackson is struggling, and one of the reasons is he isn’t getting hitters to chase.
This year, Jackson is walking hitters at a rate he hasn’t seen since 2007. Through six starts he has managed to produce a BB/9 rate of 4.46 (11.2 percent), almost a full walk higher than his career average of 3.49 and just off his 2007 mark of 4.92 (11.7 percent). On the bright side he can take solace in the fact he isn’t reaching 2006 BB/9 levels of 6.19 (14.4 percent).
The other bright side is that his walks seem destined to run back toward his norm and should run closer to his six-year average of 3.10. Maybe the biggest factor in Jackson’s dismal walk rate has nothing to do with him actually throwing strikes.
I wrote earlier that a big factor in Cliff Lee‘s emergence as an ace was making hitters chase balls outside the zone, and in every year since 2008, hitters have made less contact on Lee’s off-the-plate offerings.
PITCHf/x shows the opposite problem for Jackson.
In 2014, he’s actually hitting the zone more than he has since 2009, at a rate of 51 percent. That said, his overall swing rate is down 1.1 percent from 2013 and has decreased every year since 2011.
Jackson’s current 25.8 percent chase rate is a career worst since PITCHf/x data was utilized in 2007 and well-below his 30.3 percent career average. Jackson’s O-Swing% has been in decline the past two seasons after a high mark of 33.1 percent in 2012, which was also the year he set career bests for K/9 (7.97) and BB/9 (2.75).
In short, Jackson isn’t fooling hitters in 2014.
Jackson has never been known as a pitcher with a knack for the strike zone, but past data suggests opposing hitters have bailed him out at higher rates. This year’s numbers suggest a new approach against him or that his stuff is lacking something it did just a few years ago.
What PITCHf/x data suggests is that Jackson is throwing a wider array of pitches with average to below average success. He’s more than doubled his use of a curveball this year but has cut back on his slider—his best secondary pitch—by fpur percent.
Jackson’s changeup use—one of his best non-fastball swinging strike pitches—has had the most severe cut. He’s thrown it 2.1 percent of the time in 2014, up from 1.8 percent in 2013, but well below his 7.2 percent career average.
When Jackson takes the hill on Tuesday night against the White Sox, he’ll have a good chance to improve his O-Swing% percent in a hurry and start to reel in his walk rate.
Of the qualified hitters for the White Sox, only Adam Dunn (16 percent) and Marcus Semien (23.4 percent) are swinging at pitches outside the zone at rate below the 2014 league average of 28.9 percent. Jose Abreu (38.9 percent) and Alexei Ramirez (38.4 percent) have the worst O-Swing% rates among Chicago’s qualified hitters and swing at an overall rate almost 10 percent above league average.
To right the ship, the data suggests Jackson might want to go back to the old fastball-slider-changeup repertoire.