Even with a comparatively down free agent market this last winter, Tyler Chatwood exceeded many contract predictions when he signed for $38 million over three years with the Chicago Cubs. Despite a fairly average career to that point (ERA+ of 105), the Cubs obviously saw something they liked and targeted him as one of the first free agent signings of the offseason. And while his superficial numbers this year have been fairly consistent with his near-average career (ERA+ of 92 as of 7/4/18), he is on pace for a historically bad season based on control. Why did this happen seemingly so suddenly? And at what point does poor control bleed into the abhorrent “yips”?

It is safe to say that the Cubs had reasonably high hopes for Chatwood given their willingness to ostensibly “overpay” for his services. His six-year career (2011-17) with the Angels and Rockies certainly provided some ups and downs, however. His 2017 ended with a 4.94 FIP/4.27 xFIP, a K/BB of 1.56, and 1.1 fWAR — nothing that outwardly signifies a promising future for a 27-year-old pitcher. Eno Sarris did comment about him potentially being close to a breakout with a couple of adjustments, so it’s possible there was/is a potential breakout just beneath the surface. Despite that optimism, at the half-way point of the 2018 season, he is on pace to post a BB/9 of 8.10, nearly double his career mark to this point (4.17), and the 8th worst seasonal mark in the integration era of any pitcher with at least 100 innings. If his current BB% of 19.4 held up, he would have the 7th worst percentage in any season of any pitcher, within the above criteria. No one has had walk rates (either BB/9 or BB%) as bad as this in the last 30 years over a full season.

Chatwood has always had some difficulty with his control as evidenced by his above-mentioned career BB/9. So why has he slipped so much in his first 3+ months in Chicago? Some of the first causes we might consider in such instances would obviously be things such as a mechanical flaw or some unreported injury. Or maybe it’s the stress of moving cities, particularly to a much larger market than he is used to with subsequent increased scrutiny? You could look at a change in pitch usage, attacking batters differently, working on something specific in his repertoire that hasn’t manifested yet in any improvement. After all of these things, the nerd in me obsessed with the brain-body connection begins to think of the dreaded yips.

Since I am not a scout or a pitching coach, and do not have inside information as to any potential injuries or his psychological state, I obviously cannot evaluate the first two possibilities as potential drivers of his worsening control. His pitch usage has not changed to a huge extent but has to a small degree. According to FanGraphs, the use of his cutter has increased by 3.4% to 24.1%, with a coinciding decrease in his fastball usage by 4.2%. He has also mildly increased use of his changeup (2.9%) and decreased his curveball usage (2.1%). There doesn’t seem to be anything here to account for a major change.

His strikes thrown as a percentage of all of his pitches hasn’t dramatically changed but does show a slight decrease (58.3% in 2017 to 55.7% in 2018). The percentage of pitches he throws in the strike zone have decreased somewhat (41.1% to 37.4%). His current xFIP of 5.26 seems considerably low given his control issues, but this is largely because he has been keeping the ball in the park (HR/FB of 9.3%). None of these differences are likely to account for a near doubling of his walk rate.

It is very unlikely that Chatwood has the yips, at least anywhere near a “full blown” case. But what indication might there be if he does? The yips (or Steve Blass Disease, or the Thing, or the Monster, or numerous other names) oftentimes show up suddenly with extreme lack of control and then don’t go away. Sometimes they can be tamed for a short period. Rick Ankiel admitted to pitching drunk in order to calm them, and had a couple of decent outings doing so. The yips are hard to officially describe/diagnose; we tend to know it when we see it. Players don’t like to talk about it for fear of “making it worse.” It’s a badge of shame, a scarlet Y square on the chest of any player who may carry the label. The problem therefore becomes opening the psychological black box to try to understand what is really going on. Are the yips a binary yes/no option, you either have them or you don’t? Or is there a gradient? Are they a purely mental disruption in the brain-body continuum? Are they from a neurological problem? Something else? We just really don’t know, and we don’t have a lot of granular pitching and throwing data to help us figure it out.

The most well known “recent” example comes from Rick Ankiel’s sudden onset yips in Game 1 of the 2000 National League Division Series against the Atlanta Braves. In the moment, it was described statistically best by wild pitches that began after only allowing two hits and no runs threw two innings. After walking a batter and getting one out in the inning, he then proceeded to throw five WPs to the remaining 10 batters that he faced, only getting one out and allowing four runs. He allowed four walks in those two-thirds of an inning. In only 24 major league innings in 2001, he threw five wild pitches and had a 9.4 BB/9, spending most of that season in the minors to work out his wildness. He was a marked man and wasn’t able to pitch successfully thereafter. We unfortunately don’t have the pitch tracking data that is available to us today to further evaluate if there was any way to see this coming, though the superficial stats do not support an expected slide into psychological purgatory. In September 2000, he sported a 1.65 ERA and a 40/11 K/BB rate in 32 2/3 innings. His first two innings of the NLDS Game 1 included four baserunners (two of which were walks), and two strikeouts. Though we don’t have his pre-playoff scouting report available from the Braves or anyone else, no one would have predicted the sudden arrival of such a heinous affliction as the yips.

WPs are often cited as the main representation of the yips; they are an easy way to see increasing wildness. Chatwood has only four WPs in 73 1/3 innings this year, a rate which would put him lower than the 12 that he threw all of last year in 147 2/3 innings. We recognize that WPs can be very subjective, and research has shown that characteristics of particular catchers with particular pitchers are what determine errant pitches. This led to the creation of “errant pitches above average” (EPAA), though this stat is typically listed with catching metrics so it is difficult to isolate it for a given pitcher like Chatwood. It does, however, underscore the notion that WPs aren’t the best way to determine the yips over a larger sample, though the five that Ankiel threw in the 3rd inning of the NLDS game certainly give us a hunch of what may have been starting.

The unsatisfying answers here are that 1) there is no easy answer to Chatwood’s control struggles in 2018, and 2) given the very limited data that we have and poor definition of what the yips actually are, we don’t have any way to predict them. Despite Chatwood’s severe lack of control that has seemingly come out of nowhere, the yips appear very unlikely as a contributor. It is also possible that we will never fully know if they play a role in his performance or not.