The St. Louis Cardinals rotation has a clear leader - Jordan Montgomery. Through 15 starts this year, the left-hander has 2.0 fWAR, which is 0.5 ahead of the next closest member of the rotation - Miles Mikolas.
Now I wouldn’t blame you if you thought Montgomery had been good but not that good. He had a rough patch and some good starts but you wouldn’t expect him to be the 16th best pitcher in baseball according to fWAR, would you? But that’s exactly what he’s been.
He’s sandwiched right between Spencer Strider and Aaron Nola in fWAR this year, which is great company but not exactly the crowd you might expect Montgomery to be in. But yet here he is.
For a rotation that’s taken all kinds of heat this year, Jordan Montgomery is on pace to finish the season with 4.3 fWAR (assuming he makes 32 starts and holds his current pace), which would shatter his previous single season high of 3.2.
I want to emphasize that if you don’t check stats very often, you probably wouldn’t expect Montgomery to rank this highly. That’s because he doesn’t look like anything spectacular on the mound. He doesn’t have high velocity. He doesn’t throw a nasty breaking ball. He doesn’t even get a particularly high number of ground balls.
Yet he’s been one of the 20 best starting pitchers in baseball this year. And, really, most of his success has come from just one single pitch - his sinker.
(In the table below, remember that a negative run value is good for pitchers.)
Jordan Montgomery Individual Pitch Stats
So that’s a total run value of -3, with -10 coming from Montgomery’s sinker and 7 coming from everything else. And the left-hander’s sinker is the only pitch with a negative run value.
In fact, the -10 run value of Montgomery’s sinker is the single best run value of any pitch in the Cardinals staff. (In second is Andre Pallante’s fastball, which I already wrote about, at -8 and in third is Jordan Hicks’ sinker, which is a pitch that will come up later in this piece, at -6.)
It stands head and shoulders above the rest of his arsenal, and above every other pitch on the Cardinals staff (at least in terms of run value), but yet it doesn’t look like anything special.
So, just how has Jordan Montgomery’s sinker been so successful this year? That’s the question I want to answer with this piece.
If I told you that Jordan Hicks had a better sinker in terms of run value, it would probably be believable. I mean, that’s a pitch with crazy velocity and wiffle ball-esque movement. When you compare Montgomery’s sinker to that, it’s just kind of a bland run-of-the-mill sinker.
The metrics on it don’t look all that great to be honest. They’re fine, but nothing special. Take a look.
Montgomery Sinker vs Average
|Montgomery vs Avg||Velocity (mph)||H Movement (in)||V Movement (in)|
|Montgomery vs Avg||Velocity (mph)||H Movement (in)||V Movement (in)|
|League Average Sinker||93.4||14.6||20.5|
That’s basically a league average sinker. An extra inch of run is nice but there’s not much out of the ordinary there. So either his sinker has been extremely lucky this year or something is causing it to play better than it’s profile.
As I’m not a huge fan of leaving things to luck, especially with this large of a sample size, we can discount that theory. And lucky for us, there is something that Montgomery’s sinker does extremely well.
Spin Direction Deviation
It deviates from its expected movement pattern.
This is where spin makes a difference. And when I say spin, I’m referring less to spin rate (which is still important) and more to spin direction. And spin efficiency matters too but I’ll get to that.
The following graph gives the spin direction of Montgomery’s arsenal at release. Just focus on the sinker (the orange bar) for now.
You can see that most of his sinkers are right around the 11:00 to 11:30 mark. On average, the pitch has a spin direction of 11:00 on release. That’s pretty close to an over-the-top release point, which makes sense as Montgomery is listed at 6’6”.
Now here’s the graph showing Montgomery’s spin direction when the ball arrives at the plate:
Notice how the spin direction of Montgomery’s sinker has shifted down? Now the average is 10:00. That’s much different from his spin direction at release.
In general, this kind of deviation means the pitch is getting more arm side run and more drop than would nornally be expected from a sinker released at 11:00, and that movement is coming late. You can call it late break or seam-shifted wake but that’s what has helped Montgomery’s sinker play up.
Now, I started that last paragraph with “in general” because that principle doesn’t always hold true. Spin direction deviation doesn’t always lead to more movement than expected.
On Monday, as I was doing some research for this piece and for my own interest, I stumbled upon a great article written last year by Michael Ajeto of Baseball Prospectus. I linked it and I highly suggest that you give it a read, but to save you some time for now, I’ll sum things up.
Ajeto points out that axis deviation (or spin direction deviation) isn’t the sole cause of seam shifted wake. He uses two pitchers to make his point. The first is Marcus Stroman, who is generally considered a master of seam shifted wake because his pitches have large spin direction deviation.
The problem with that conclusion is that his pitches don’t really move more than expected because he has a low rate of active spin, meaning that he puts a lot of gyro spin on his pitches, and gyro spin, as we know, basically prevents a pitch from moving at all.
So because Stroman’s sinker is so inefficient (59% active spin), there is less Magnus force acting upon it so the seams don’t have as much opportunity to interact with the air, which means that the spin-direction deviation doesn’t really create extra unexpected movement.
The counter example is Spencer Turnball who does see extra movement from his axis deviation because his sinker has more active spin (78%).
So, the main theme is really that axis deviation in isolation doesn’t tell us whether or not a pitcher is experiencing seam-shifted wake, but rather, axis deviation should be combined with active spin to give us a better idea of what’s happening to the pitch.
That’s just the short version, though. If you find this interesting, you should absolutely read the full article to get more in depth. But let’s bring this discussion back to Montgomery now.
Ajeto uses stats like expected induced vertical break and expected horizontal movement that I’m not privy to so I’ll have to settle for comparing the active spin of Montogmery’s sinker with the active spin of the pitchers mentioned in the article to see if Montgomery truly does create additional movement.
And, lo and behold, Montgomery does get plenty of active spin. His sinker gets 86% active spin, which is above even Turnbull’s rate of active spin, so we can expect that, since the pitch limits it’s gyro spin, it is experiencing seam shifted wake due to the fact that the seam have more opportunity to interact with the air and get the full benefit of the spin-direction deviation.
So, to make this simple, that means the Montgomery’s sinker is deceptive. It may not have excellent metrics but it does deceive hitters by moving more, differently, and later than they are expecting.
The Supporting Pitch
But I’m not going to stop there because I suspect that there’s another factor at play in the success of Montgomery’s sinker. And that’s his changeup.
Again, on the surface, this doesn’t look like a great pitch. It has well below average movement in both directions and it’s movement pattern deviates less than 6 inches in either direction from Montgomery’s sinker. Generally that’s not a great sign. A 9 mph velocity difference is solid, but overall there’s not a ton to be excited about on the surface. The difference, however, lies in the spin direction once again.
Whereas Montgomery’s sinker gets additional run and sink due to his axis deviation, Montgomery’s changeup actually gets additional cut and ride.
Yes, I know, that’s weird. Changeups don’t cut or ride. At least not usually. Usually they run and sink, just like sinkers. And while Montgomery’s changeup does do that, it doesn’t do that as much as the hitter expects it to.
I’ll provide the spin direction graphs again for proof. Notice the green bars this time. Here is the spin direction upon release:
And here’s the spin direction at the plate:
The pitch goes from a heavy concentration at 11:00 at release to more of a spread out direction between 11:00 and 11:30. The average of both is still listed at 11:00 but we can see that the pitch has a tendency to get a little bit of late cut and late ride. It’s not a ton but even a little bit counts, especially when that little bit of late movement is in an atypical direction.
That really just helps Montgomery’s sinker play up that much more. The two pitches are meant to build on each other and look similar so when one pitch is getting additional unexpected run and sink (as compared to what would be expected from the pitch’s spin direction at release) and the other is getting additional unexpected cut and ride, it has a great effect.
As you recall from earlier, the run value of Montgomery’s changeup isn’t great but the other metrics provide better support for it. A .307 wOBA, .320 xwOBA, and 37.6% whiff rate are all solid measures. (Run value can be distracted a bit by context so it’s not always the best measure even though it generally provides a decent look at a pitch in a large sample.)
The unexpected late movement of each pitch makes both of them strong offerings in isolation, and it makes them better than they look on paper, but both pitches are much better off with the support of the other.
Other Pitchers of Note
There are a few other things to point out when discussing seam shifted wake and axis deviation. In general, it’s a good thing, but there are always other factors at play. Location and command matter. So does pure stuff because even though seam shifted wake can enhance a pitcher’s stuff beyond what it may appear to be, it doesn’t matter if the stuff simply isn’t that good to begin with.
Take Adam Wainwright for example. I don’t want to keep bashing the guy because he’s been bashed plenty this year. But his sinker has been a terrible pitch this year despite having practically the same spin rate deviation and active spin as Montgomery’s sinker. The .534 wOBA, to me, is caused by the pitch simply not having enough juice anymore. And when that’s combined with less extension, it’s simply not a good offering regardless of the seam shifted wake.
On the other hand, there’s Jordan Hicks, who also has a spin deviation from 1:00 to 2:00 and 85% active spin. Pair that level of seam shifted wake with an 100 mph sinker with already great movement, and that just gives it that little bit of extra movement and deception that makes it even better.
The last pitcher I want to mention is Jake Woodford, whose sinker actually sees a deviation from 1:15 to 2:30. That’s even more deviation than Montgomery and Hicks!
The pitch hasn’t been too effective for him but it’s still the only pitch in his arsenal with a negative run value and it’s by far his best fastball. A .357 wOBA may seem high but it’s much lower than the .789 wOBA Woodford has allowed against his four-seamer.
Neither pitch has an exceptional movement profile or great velocity but Woodford’s sinker benefits from the extra movement and deception provided by seam shifted wake. His fastball does not. The pitch cuts a little bit but mostly doesn’t deviate it’s spin direction from start to finish. If he could cut his fastball more it would be a viable pitch, but he doesn’t and the pitch gets hammered as a result.
I’m usually more of a proponent of pitch mix tweaks than totally reworking a pitcher’s arsenal but Woodford should probably just stop throwing his four-seamer entirely. His sinker is the much better offering and really the only fastball he throws that is good enough to not get completely hammered. The pure stuff still isn’t great but he does benefit from seam shifted wake.
Again, seam shifted wake isn’t some magic potion that fixes a bad pitch. Rather it’s something that helps a pitch play up with increased movement and deception.
A pitch that moves more, and later, than expected is an asset.
To answer the question I asked at the beginning of this piece, how is Jordan Montgomery’s sinker successful? Because it’s deceptive.
In an age where we often like to look for raw stuff in a pitcher, it’s still possible for a pitcher with middling stuff to be deceptive enough to pitch really well. That’s the story with Jordan Montgomery. His sinker doesn’t have the best profile from a pure stuff perspective but seam shifted wake helps it move more (and differently) than a hitter is expecting it to. That’s deception and that has helped the pitch play beyond it’s perceived limits.
Identifying spin direction deviation and pairing it with active spin can help us get a deeper understanding of a pitch and what makes it successful (or not successful) than a simple look at velocity and movement.
It’s still hard to quantify deception but this is a way to at least understand if it’s playing a role and where it’s coming from.
Thanks for reading, VEB.