Jared Eickhoff’s Off Speed Struggles
It is hard to pinpoint positives in this year’s Phillies season. The hitters haven’t hit, the bullpen spent about a month blowing every game that was remotely close, and a young starting rotation has seen every member take a step back. Arguably the best pitcher of that group is Jerad Eickhoff, but through 2 months he has yet to really look like himself.
Before talking about Eickhoff’s main pitch, it is important that we talk about the pitch he is not throwing, his changeup. Jerad Eickhoff’s changeup has never been a good pitch. It has about 7 miles per hour separation from his fastball and moves armside and down a little bit less than his two seam fastball. The pitch is somewhat slightly better than a batting practice fastball. Over his first two seasons he threw it 6.9% and 5.2% of the time. He got a decent number of swings and misses on it, but it also got crushed a fair bit too. This year, according to Brooks Baseball, he has thrown 7 changeups, of which 5 were in his first start of the year. Eickhoff has always struggled vs left handed batters because of how poor his changeup is, but this year he is allowing them to hit .280/.358/.496, and they are walking in 10.1% of their plate appearances vs him (righties walk at a 3.8% rate). The problem isn’t that he is missing a bat missing changeup, but that he is missing something else to keep left handed hitters honest. What has happened is a drop in how many curveballs left handed batters are swinging and missing at, and as his walk rate goes up, he is not working as deep into games — but more on that later.
Eickhoff’s primary pitch has always been his curveball. Since coming to the majors, this has been augmented by a slider that is also a pretty good pitch. Both pitches have had the same problem.
The slider is dropping two inches less, and the curveball is dropping 3 inches less. When we account for gravity, we see those drops become 5 inches less and 6 inches less respectively. What does that mean for Eickhoff’s success? Here is the average vertical location of those two pitches over the past three seasons.
That is not to say he is hanging all of his curveballs, but he is not burying them down and out of the zone. The same thing is happening with the slider. This seems to have directly impacted his ability to miss bats, as his swinging strike rate with both pitches has decreased sharply.
While Eickhoff’s strikeout rate has not changed much (20.6% in 2016, 20.2% in 2017), Fangraphs has his swinging strike percentage dropping from 9.4% to 8.0%. This inability to bury his pitches out of the zone for strikes has caused hitters to swing at fewer pitches out of the zone, increasing the number of pitches he has to throw in the zone, where batters are making more contact. He isn’t throwing more pitches per plate appearance, but he is walking batters more as they don’t chase the pitches out of the zone.
Clearly the solution to the curveball and slider problem is to throw them like he used to, but that takes knowing what is wrong. There are a couple of potential causes. The first is the spin rate of the pitches, unfortunately the spin rate data set for 2017 is missing from the data dump at Baseball Savant, and the blotches of a plot are impossible to make any real conclusions. What we do have is this.
I have removed his other pitches from the graph, but all are stable from year to year. Now part of this could be MLB Advanced Media’s change in tracking data. Sites like Brooks Baseball have looked to normalize this, but we have to account for potential error. However, if Eickhoff is throwing both pitches harder, it would help explain why we are seeing less movement on them.
I don’t know whether the removal of the changeup from his arsenal is a developmental decision from Eickhoff and the coaching staff (perhaps to devote that energy to other things) or if he just doesn’t have confidence in the pitch and doesn’t want to throw it. The answer to that question determines whether we will see the pitch again. More importantly than bringing back a changeup of some sort, Eickhoff needs to turn his breaking balls into impact pitches again. His fastball is straight, and while his two seamer is good at generating ground balls, both pitches are bad at missing bats. He needs the breaking balls to keep hitters honest. Until he can make those improvements, teams are going to load up with left handed bats against him, and he is going to look more like a #5 starter than the middle of the rotation workhorse he looked like coming into the year.