One of those baseball facts that might stick with me forever is that, after getting traded from the Mariners to the Astros, Randy Johnson put up a 1.something ERA. Specifically, including the playoffs, Johnson appeared in 13 games with Houston, and his ERA was 1.42. To be that dominant, in that era, under those circumstances, after having struggled before the deal — well, I don’t know what else there is to explain. I haven’t forgotten about it for 20 years. I’m sure I’ll remember for at least 20 years more.

We’re living in the middle of a similar fact. One that’s gone on longer, one that must be considered even more impressive. After getting traded from the Tigers to the Astros, Justin Verlander has put up a 1.something ERA. Specifically, including the playoffs, Verlander has appeared in 23 games with Houston, and his ERA is 1.36. In Verlander’s most recent start, against the Yankees, he allowed one run. That’s right on his season average — he’s allowed 12 runs over 12 starts. After allowing seven runs in the season’s first month, he allowed five in the second. Hitting Verlander of late has been more or less impossible.

Verlander was traded last summer, and was immediately good. We’ve already gone through a bunch of stories examining his turnaround, highlighting, especially, the improvement of his slider. That was a common conversation last fall — the one about how Verlander got better by making use of Houston’s slow-motion cameras. Yet Verlander only continues to grow. He remains, you could say, a work in progress, and he’s made a further adjustment in 2018 to get the most out of the pitches he has.

Over the course of his eventual Hall-of-Fame career, Verlander has possessed a dominant changeup. He’s possessed a dominant curveball, and he’s possessed a dominant slider. The pitch that will be remembered for decades, though, is the dominant fastball. So much of the whole Verlander story comes down to the fastball, how it refuses to lose any speed, how it can brush triple digits in the top of the ninth. From the beginning, Verlander has thrown heat, and as we’ve come to understand pitches better and better, we’ve seen that Verlander succeeds by throwing a rising four-seamer around the upper part of the zone.

In general, current Verlander doesn’t look very different. If you were to watch him now, you might not think anything has changed from his earlier peak. Of course, some tweaks are obvious, and some are more subtle. Here’s something subtle. Among starting pitchers, Verlander’s four-seam fastball has commonly ranked in the upper fourth, in terms of vertical movement. In other words, it’s consistently generated more rise than average. In this season, however, Verlander’s four-seam fastball ranks in second place, behind only Marco Estrada. He already generated rise. Now he’s getting more. The more rise a four-seamer gets, the harder it is to square up.

How does a pitcher like Verlander do this? The easiest way to analyze what’s going on is by looking at a plot from Brooks Baseball. Here, then, are Verlander’s month-to-month vertical release points:

It’s not hard to spot the trend Verlander and the Astros have worked to reverse. Last year, after arriving in Houston, Verlander started throwing from a higher slot. This year, the slots have gotten higher still, which can’t be a mistake. Granted, Verlander was very good in 2016, so it’s not like there’s only one way for him to succeed. But this is an adjustment that’s taken place in an Astros uniform. Verlander’s arm is moving back up to where it used to be, before the core muscle injury, before the intentional drop to three-quarters. This allows him to pitch in a particular way.

I’ll borrow now from Texas Leaguers. Here’s a comparison of Verlander’s release points in May 2017 and May 2018:

Here are fastballs from May 2017 and May 2018, with the lower slot being from last year:

And here are sliders from May 2017 and May 2018, with the lower slot being from last year:

What can be the consequence of someone raising his arm slot? For one glimpse, I’ll return to Brooks Baseball. For Verlander’s fastball, slider, and curve, here are his year-to-year average vertical movements:

When a pitcher raises his arm slot, he can be more able to move pitches up and down. Breaking balls are more 12-to-6; fastballs have less run. What we can see with Verlander is more vertical separation. Now, the slider has changed for a couple of reasons — that isn’t just because of the arm-slot adjustment. But the separation in vertical movement between Verlander’s fastball and slider is the greatest it’s been since 2012. The separation in vertical movement between his fastball and curve is the greatest it’s been since 2012, as well. Verlander has always had these pitches, yet they’re ending up in slightly different places.

To drive the point home further, here’s another comparison between May 2017 and May 2018. For each Verlander pitch type, you’re seeing horizontal and vertical movements.

The slider has shifted substantially. Again, we talked about that last fall. That’s a part of the story here. But for the purposes of this particular post, focus on the fastballs. It’s not so much that Verlander has added a lot of rise; it’s more that he’s eliminated fastballs that don’t get much rise. There’s a shift up and toward the center. Verlander is throwing exclusively four-seamers. He’s always thrown four-seamers, but from a lower arm slot, sometimes he’d get more two-seam behavior. With the Astros, and especially now, Verlander is getting and staying on top of the ball, and his four-seamer is looking overwhelming.

So Verlander is back around a career-high arm slot. In a sense, he’s pitching how he used to. In another sense, he’s taken that old approach and tweaked it. For the final image in this article, take a look at Verlander’s pitch-type zone rates, covering the previous decade:

Verlander is getting plenty of separation between his fastball and his breaking balls. But now he’s pitching even more fastball-first, in that he’s using his fastball more aggressively. Verlander’s fastball has a career-high zone rate, by a large margin. He’s not the least bit afraid of the pitch staying over the plate. And because the heater is so good, that allows Verlander to mostly keep his breaking balls low. The curveball has its lowest zone rate. The same goes for the slider. The fastball is already hard to hit, and, because of that, the other pitches have become extra unhittable. Verlander is working up and down better than ever before, and as a result, these days he doesn’t even need a changeup. He has more than enough to get hitters out.

When ace-level starting pitchers reach their mid-30s, it’s usually a story of survival. A story of how a pitcher has to make some adjustments if he wants to be able to keep his job. In this and in so many other ways, Justin Verlander is an exception. He’s not pitching to keep a job. He’s pitching to win another award. Maybe another two or three. At some point, it’s inevitable that Verlander is going to break down. No one is able to do this forever. Verlander’s trying. And he’s doing an admirable job of it.