Something happened to Hideki Okajima last season.
Actually, two things happened to Okajima last season. First, his BABIP went through the roof, catapulting to a shocking .357. Second, his plate discipline indicators all took slight hits, which compounded to create a major deficit in his strikeout and walk rates.
Whether this was the cause of back and hamstring injuries or an overall decline is up for debate.
In fact, Rob Bradford has a great take on the subject over at WEEI.com that is well worth the read.
(http://www.weei.com/sports/boston/baseball/red-sox/rob-bradford/2011/01/01/can-okajima-rebound-tracing-his-decline-and-p)
Before getting into a more protracted analysis, I’ll take the liberty of discussing some of Bradford’s finer points. In the article, Bradford breaks down Okajima’s fastball struggles at length, citing his failures at locating the zone, his struggles with BABIP against righties, and a dip in velocity.
While I concur with most of his points, the single critique I have is the role of fastball velocity and overthrowing on his location struggles. After reviewing the statistics in the article, he didn’t seem to have greater problems with location during pitches with increased velocity compared to those at lower velocities. Okajima’s batting average against righties didn’t seem to have a noticeable rise when dialing up the fastball, nor did it seem as if he located the pitch any worse.
That said, my interpretation of the evidence leads me to believe that overthrowing didn’t have much to do with Okajima’s struggles.
Other than that, I agree with all the other major points. In particular, I throw my support behind the idea that Okajima’s command problems were at the root of his struggle in 2010. Considering that Okajima is a low-velocity hurler, he may have been at greater risk of a regression should his location go in the tank.
The primary advantages of velocity are that it gives a pitcher room for error in the strike zone while putting pressure on hitters to make their secondary pitches more effective.
Though there is no definitive study confirming this theory, there is evidence to suggest that it may have effects on BABIP. In addition, it makes sense that, at low velocities, we may see an increased negative effect of lost location. There is a wealth of knowledge that shows the effect of location on BABIP.
Theoretically, if a pitcher threw at high velocity, they would be able to these location-related hits via whiffs, inducing pop-ups and opposite-field fly balls, or by weaker contact.
If a pitcher threw at low velocities, they would not be able to avoid these location-related whiffs.
Theoretically, they would not be able to induce these pop-ups, opposite-field fly balls, or weaker contact.
Theoretically.
Could this have happened to Okajima?
Probably.
More importantly, however, was it the injuries, age-related decline, and/or a temporary, BABIP-sample size glitch?
If I were to put money on it, I would blame the off-year on the injuries and sample size discrepancies. However, injury has always been another word for age-related decline, so the two go hand-in-hand.
That said, the BABIP issue probably has something to do with the injuries. While it always seems impossible for sabermetricians to admit that BABIP is anything other than luck, I, for one, believe that pitchers — at the very least — have the ability to negatively affect their BABIP.
Location is a major contributing factor for hitter’s BABIPs, so it makes perfect sense that a pitcher who struggles with location would post a high BABIP. Hamstring and back injuries would affect a pitcher’s release point, which in turn would affect location. If Okajima was having problems locating a mediocre fastball, he would certainly qualify among those at high-risk of posting a high BABIP.
As is usually the case, everything is interrelated and we arrive at the conclusion that all three factors were at play. Okajima is getting older, which makes him more susceptible to injury, which will decrease the effectiveness of his pitches.
If this analysis is correct, Okajima should be able to bounce back — as long as he is healthy.
Perhaps the one nagging problem I have with this analysis is that there is the possibility part of Okajima’s command issues were by design.
Specifically, this has to do with the fact that Okie had a large increase in O-Swing percentage this past season, rising from 24.6 to 31.8. Many pitchers who see an increase in their O-Swing will also throw more pitches out of the zone, because hitters are chasing. Therefore, it is plausible that Okajima was missing the strike zone because of approach, not because of injuries or general ineffectiveness.
While this would debunk the theory of injury being the prime mover in Okajima’s regression, it would not change the bottom line. In fact, it would be just as easy to rebound from — if not more so.
As for projections for next season, that’s where it gets a little discouraging. Having posted a 4.50 ERA and 0.0 WAR — not to mention a favorable rebound forecast — one would expect a big recovery for Okajima.
Unfortunately, we see quite the contrary. If Okajima were to recover all his lost zone percentages (while losing his O-Swing gains) and BABIP losses, he would still be expected to post just a 4.15 ERA.
Why only a 0.35 gain in ERA against 2010? According to our numbers, Okajima was supposed to have posted a 5.013 ERA last season with a 6.93 K/9 rate and 3.469 BB/9 rate.
In other words, Okajima should be good enough to hold down a middle relief job, but won’t be the late inning stalwart he was in 2007 and 2008. Expect a WAR of about 0.5 and expect a lot of lefty work.