Who has the best four-seam fastball on the Astros?

Mar 27, 2023 - 4:27 PM

Houston Astros at Philadelphia Phillies" src="https://cdn.vox-cdn.com/thumbor/IsN7WU7v867vO-I0kNzIo7Mfjd4=/0x0:3361x1891/1920x1080/cdn.vox-cdn.com/uploads/chorus_image/image/72119387/usa_today_19348841.0.jpg" />

With Opening Day fast approaching, I felt like now was the ideal time to start a little project I’ve desired to write about in recent months: The best pitches on the Astros’ pitching staff—specifically, the pitchers who figure to start the season on the active roster. So, I’ll concentrate on those best pitches for the next few weeks, starting with four-seam fastballs.

Beauty is sometimes in the eye of the beholder and is no different in baseball. Former Astro Hunter Pence, for example, wasn’t the most aesthetically pleasing player to watch, but you couldn’t deny his results. Luis Garcia — before the pitch clock implementation — had his infamous “rock the baby” windup. While some found the unusual motion a unique aspect to be celebrated, others argued it was basically a balk. Again, the eye of the beholder matters a bit here.

But what exactly determines the best version of a pitch? Is it primarily velocity and movement, or lack thereof? How about results, actual and expected? By run values? Swings and misses? The overall look of it?

Ultimately, I think it is best to approach this best pitch exercise on a case-to-case basis with a range of factors to consider. Results in this exercise hold a fair amount of sway as baseball is a results-oriented business. Velocity is also important in addition to overall movement, or lack thereof. I also have to consider how often the pitch is used and how it is utilized in relation to the rest of a pitcher’s arsenal. It requires a balancing act of sorts as some of the results appear great, but the usage rates are low. Then there is the potential if it has the look of a high-quality pitch, even if the results are lagging for now. For this list, there is a heavy leaning toward relievers considering how well four-seam fastballs play up in shorter spurts, except for the top guy.

Without any further adieu, let’s start with the fifth-best four-seam fastball on this roster.

5. Rafael Montero

There are justifiable reasons to believe that the Astros overpaid a bit to retain Rafael Montero’s services, especially over three years. For one, Montero has yet to post back-to-back an ERA below 4.00 in his major league career, which dates back to 2014 with the Mets. The lack of consistent success up to this point is why a three-year contract felt risky, with the usual reliever volatility issues also taken into account.

The organization unlocked something within Montero by having him elevate his four-seam fastball more often and letting it rip. It wasn’t a mere coincidence that last season was the first time since 2015 that Montero had a sub-.300 xwOBA and a whiff rate higher than 30% from his four-seam fastball.

The Astros have had success by having various pitchers embrace this approach with their four-seam fastballs, as you’ll read throughout this list. And it is hard to argue against the results as the club had the second-lowest wOBA (.236) in baseball on four-seam fastballs thrown in the upper regions of the strike zone. Only two clubs threw more four-seam fastballs in that same area than Houston. Presumably healthy, this approach is a key reason behind Montero’s resurgence, and it could help him break those pesky consistency issues that have plagued his career.

4. Ryne Stanek

While walks remain an issue for Ryne Stanek, the right-hander had arguably the best season of his career in 2022, thanks to his improved four-seam fastball. The numbers behind the pitch (usage, movement, spin rate) didn’t change that much, but where he used it did.

An elevated four-seam fastball to generate more whiffs, you don’t say? Why does that look so familiar? /s

In all seriousness, Stanek’s four-seam fastball had noticeably improved results in 2022 compared to 2021. By run values among current Astros pitchers last season, his four-seam had the second-best standing on the club. Yes, you read that right. By elevating it higher in the zone, Stanek has turned the pitch into a more viable offering to generate more swings and misses, keeping it out of the opposing hitter’s sweet spots. There’s an obvious pattern here with the Astros and elevating four-seam fastballs.

3. Hunter Brown

By run values, Hunter Brown’s four-seam fastball graded out as the best on the staff among current Astros at negative-three runs. The results from the pitch were encouraging, with a .233 SLG and .246 wOBA in a small sample. This may remain the case in 2023 if he continues to pitch as he did to finish last season. The caveat here is that a bulk of his work in the majors occurred as a reliever when his stuff would play up a tick or two, considering the nature of shorter outings.

The compelling aspect of Brown’s profile is that he didn’t elevate his four-seam as often as his contemporaries on the roster. He’s not afraid to utilize his fastball throughout various areas of the strike zone to both left- and right-handed hitters. I am curious to see if this approach is altered somewhat as the type of velocity and noticeable vertical movement Brown possesses on his four-seam fastball could unlock something further here with his command. That kind of development would be scary to watch, as his four-seam fastball is already among the best on this staff, considering the velocity and movement it already possesses.

2. Bryan Abreu

Bryan Abreu had a four-seam fastball that averaged around 97.2 miles per hour last season en route to a breakout 2022 season. It is GIF-able, but I would be remiss not to point out that Abreu’s four-seamer in terms of results (.348 wOBA/.355 xwOBA) wasn’t particularly noteworthy compared to some of his teammates. A solid pitch no doubt, however, I wouldn’t classify it as the best four-seamer on the staff.

Instead, I classified it as the second-best four-seam on the staff. But why?

Abreu’s four-seam arguably serves best as a setup for his devastating slider, which is the offering that drove last season’s breakout. While his fastball is a quality offering in its own right, it was not his premier pitch. To compare, Phil Maton threw his four-seamer at a roughly similar rate last season — 43.2% compared to 45% — and had better results as evidenced by his .331 wOBA/.316 xwOBA. In run value, Abreu didn’t grade out particularly well at plus-two runs.

That said, Abreu’s four-seam offers some appeal moving forward, especially if he begins to elevate it a bit higher in the zone, as the above GIF indicates, and as a few of his current teammates already do. This particular ranking is more about potential, as the right-hander arguably has the highest ceiling of any reliever currently on the roster. If he unlocks his four-seam fastball further in unison with that wipeout slider, look out. There is an All-Star closer potential here with Abreu.

1. Cristian Javier

With Verlander now residing in Queens, there is little doubt who has the best four-seam fastball on the staff: Cristian Javier. The now-infamous “invisiball” has helped propel Javier’s career to new heights in a relatively short amount of time. While run values don’t grade out his four-seam as well as one would initially believe (negative-1.2 runs in 2022), it is a key component of why he is so successful, even without top-end velocity. As I detailed here in December, Javier has truly grown as a pitcher in front of our eyes, and his four-seam performance is a key reason. Last season, he did a tremendous job limiting the type of impactful contact that can ruin an outing, as evidenced by a barrel rate that declined by 4.3% from 2021 into 2022. Hitters also chased the pitch more than ever before.

While lacking the high-end velocity to blow away opposing hitters, Javier more than compensates by how well he locates his fastball now along with the deception and backspin he generates due to his delivery. Javier’s method is more akin to an art form, if you will, compared to his contemporaries. While I always enjoy watching a pitcher pump triple digits past an opposing hitter, there is a different kind of appreciation for how Javier produces his results with “lesser” velocity.