Visualizing Jered Weaver’s Hittability

It’s not just a spring-training blip anymore. For one or two games, you can dismiss a pitcher working with reduced velocity. Sometimes mechanics can be slightly off. Sometimes a pitcher can just be under the weather. Jered Weaver’s gone beyond that. His velocity was way down in spring training, and it’s carried over into each of his regular-season starts. Weaver is down a full three ticks, and that’s a dramatic decline between years. Unsurprisingly, he’s been bad — he’s struck out just one of every 10 hitters. One season ago, his rate was twice as high.

Between years, for starting pitchers, the biggest fastball velocity drop belongs to Derek Holland, and he’s on the disabled list. The second-biggest drop belongs to Henderson Alvarez, and he’s on the disabled list. The fourth-biggest drop belongs to Homer Bailey, and he’s on the disabled list. Weaver owns the third-biggest drop, and he says he feels fine. Which means there’s either something wrong that doesn’t hurt, or this is just what he is. This isn’t what he wants to be.

Said Weaver after losing again Sunday:

“I’m pretty much serving B.P. up there now. I have to work with what I’ve got.”

Maybe you don’t need Weaver to say anything. His 6.29 ERA speaks for itself. The .552 slugging percentage he’s allowed so far speaks for itself. His halved whiff rate against fastballs speaks for itself. Maybe the only person still in denial is Weaver’s catcher:

“He’s throwing not much different than last year,” Iannetta said. “His stuff is good. He’s making a few mistakes over the middle of the plate. This little funk he’s in, whatever it is, I’m sure it’ll pass.”

One way to interpret that would be that Weaver still has deception working in his favor, such that his pitches don’t look that much slower, but everything else suggests otherwise. Weaver is throwing different from last year. Maybe his catcher just hasn’t noticed because none of the pitches have made it all the way through the strike zone to the glove.

You don’t need me to tell you that Weaver has been hittable. All the data already shows it. But, conveniently, some new information just showed up on our leaderboards, some information that allows us to compare Weaver to the league and to himself. Firstly, we have data on batted-ball direction, splitting the field into thirds. So you can see, for example, pull rate for or against. And secondly, we have data on batted-ball quality. This is not new data, but it’s new data to us. And while it’s provided by Baseball Info Solutions, and not StatCast, meaning there’s some human error involved, there’s no reason to think the data is bad, and it extends years into the past. We’ve got softly-hit baseballs, hard-hit baseballs, and medium-hit baseballs.

Let’s put these numbers to use. Jered Weaver, over the course of his career, compared against league-average starters:

The graph has three different lines. In green, you see pull rate, relative to the average. This gets complicated — not every pulled baseball is a well-hit baseball — but there can be significance in big swings. Used to be, Weaver was in the vicinity of average. As his pitches got slower, his pull rate went up. So far this year, it’s leaped forward, to 36% higher than the average mark. Seems pretty intuitive. Hard to imagine a hitter being late to get around against this version of Weaver.

In red, we have soft-hit rate. There’s obviously an inverse relationship between soft-hit rate and hard-hit rate, but because there’s also a third category in between, the two aren’t necessarily directly tied. The trend here is obvious, and it’s mirrored in the opposite direction by the highlighted hard-hit-rate line.

Which is the thick blue one. Early in his career, Weaver allowed his share of good contact. As he gained experience and command, he was better able to avoid the barrel. But this year, it’s all gone away, after hints of the same in 2014. Again, you already knew this, even if you didn’t already know this, but I personally enjoy looking at even known things with new information. Just to drive the point home, Weaver’s percentile ranks in hard-hit rate, where higher means fewer hard hits:

• 2011: 93rd percentile
• 2012: 98th
• 2013: 100th
• 2014: 79th
• 2015: 17th

What made Weaver good has been missing. What it looks like is that, somewhere between 83 – 86 miles per hour, he crossed a threshold. His pitches simply got too bad to survive at the highest level. That’s too simplistic of an explanation, and Weaver would be effective again if he, say, located every pitch where he wanted, but maybe his margin of error is too small now. I don’t know. Weaver doesn’t know. Nobody knows what to do with this, because while it isn’t literally unprecedented, it might as well be. Pitchers don’t get to the majors throwing like this. Weaver will get a long leash, because of everything he’s accomplished, but if he doesn’t find more strength, it’ll be fascinating to watch his attempted adjustments.

I mean, maybe it’s just that he’s hurt. That would be easy enough, if unfortunate. Everything about this is unfortunate, but, Weaver’s risen to challenges before. It’s interesting to note he’s topped out at 98 pitches. Last year he reached 100 pitches 23 times. Maybe the Angels will shorten his outings, to try to let him air it out a little more. Or maybe Weaver will just shorten his own outings, because he isn’t good enough to push past the century mark.

As Weaver lost his fastball, the silver lining was that he still wasn’t getting hit around like it looked like he should’ve. The deception was still there to a sufficient degree. Now he’s lost more fastball. And now the hitters are seeing it.