The Astros’ Grand Fastball Experiment

No team’s batters have ever seen fewer four-seam fastballs than the Houston Astros this year. Few teams’ pitchers, meanwhile, have thrown fewer four-seam fastballs than the Houston Astros this year. This all has something to do with changes in baseball, yes, and also with the personnel on this current team. But there’s also a wrinkle to the thing that tells us a little more about why these trends are happening, and why the Astros are at the forefront in both cases.

First, take a look at where the Astros rank when it comes to four-seamers seen and thrown. They’re the blue dot in the graph below. Here’s the Tableau link, if you want to poke around. You’ll notice that two-seamers were classified more often after 2010 when you do so.

Talk to the man at the center of both of these trends, and it’s not such a big deal. “Everything like that is based on who you have on your team,” Brian McCann said. “You still have to pitch, and the name of the game is to have the ability to pitch to the hitter’s weakness. If you can pitch to that weakness, you have an advantage.”

Pitcher Brad Peacock was succinct: “I’m definitely playing keep away,” he laughed. He’s throwing the fewest fastballs of his career, like many other Astros. In fact, that’s a league trend. And teammate George Springer has noticed. “That’s a league-wide thing,” he told me. “A lot of guys are starting to go to the two-seamers because of the downward action and run, makes it harder to square up. The four-seamer, traditionally, is a little easier to square up… The league as a whole is starting to go to a lot more stuff that has deep downward action and is not that close to the plate.”

League Pitch Types by Season
Year Four-Seamers Sinkers Breakers Offspeed
2010 39.6% 18.3% 36.3% 12.9%
2011 37.6% 19.4% 37.1% 12.0%
2012 34.5% 22.2% 37.3% 11.5%
2013 35.6% 21.6% 37.0% 11.6%
2014 35.1% 22.1% 36.6% 11.8%
2015 36.7% 20.8% 36.7% 12.1%
2016 36.4% 20.2% 38.0% 11.8%
2017 35.6% 19.9% 39.4% 12.0%
SOURCE: PITCHf/x

Though the league trend is possibly there, it still doesn’t explain the Astros, who are seeing almost an extra 10-plus percentage points fewer four-seamers than the league average. They are at the extreme.

Pitchers generally play keep away to avoid the barrels of powerful hitters — and the Astros’ hitters are powerful. Listen to Springer talk about his rookie season, and you get a sense of the process. “I first came up, and I was facing Garrett Richards, a guy that throws 100 and his ball does all this stuff… [but] he kept throwing me sliders, and I kept striking out,” the Astros outfielder said. “I was talking to Scott Feldman, and I’m like, ‘Why doesn’t he throw me any fastballs?’ ‘Because you hit them!’ [he said]. I sat back and thought about it, and that’s exactly how I would approach myself. It makes sense.”

So power is part of it, but it doesn’t account for everything. While the Astros have the league-leading isolated-slugging mark, the next three teams on the list of the fewest four-seamers this year — the Royals, Braves, and Angels — are not a fearsome threesome. There’s something more going on.

Even Springer himself will add to his own story. “I’m a guy that likes to hit any pitch,” he continued. “It makes sense why guys are throwing slider after slider after slider to a lot guys. Guys will make mistakes because they’re trying to be too cute with it.” That’s one way of looking at it. Josh Reddick’s characterization of his approach offers another perspective: “Finding your location, if you got it first pitch or fifth pitch. [I] just try to focus on a zone I like.”

Talk to Houston hitting coach Dave Hudgens, and he puts it all into focus as only a hitting coach who espouses patience can. “It’s not just four-seamers up they’re looking for,” he said of his guys. “Look for a breaking ball up and you can do some damage, too. Try to avoid spin down. They’ll make adjustments. We do see a lot breaking balls, but try to find your zone and attack in it.”

Ah-ha. In the same way that the league makes the most powerful contact on pitches up in the zone, the Astros seem to be a team that likes to drive that high pitch. That’s their location, and four-seamers are usually thrown high in the zone. Take a look at the average pitch height by pitch type this year first.

Average Pitch Height by Pitch Type
Pitch Type Average Pitch Height (ft)
Four-Seamers 2.61
Two-Seamers 2.35
Cutters 2.24
Sliders 1.90
Changeups 1.87
Curveballs 1.86
Splitters 1.67
SOURCE: 2017 Statcast

The Astros are 25th in baseball in pitches seen high in the zone, so it’s not surprising to find that they aren’t getting many four-seamers. Those things go hand in hand. Once they do get pitches they like up there — perhaps the mistakes Springer references, since pitchers are mostly trying to throw low to the Astros — they swing, and they do damage. They rank seventh in slugging percentage on high pitches with a .505 number, but what makes them so brilliant is how they combine that ability to murder the high pitch while also making good contact overall.

High Pitch Slugging Teams, by Strikeout Rate
Team High Pitch Slugging % Strikeout %
HOU 0.505 17.7%
BOS 0.482 18.0%
WSH 0.569 19.5%
MIA 0.479 20.2%
TOR 0.585 20.7%
CIN 0.483 20.9%
NYY 0.520 22.5%
ARI 0.538 22.9%
TEX 0.619 24.1%
OAK 0.538 25.0%
Top-10 teams by slugging percentage on pitches high in the zone, sorted by team strikeout rate.

You’d only really say that the Nationals and Red Sox share this ability to make good contact and slug on high pitches at the same time. And yet the Red Sox and Nationals are in the top 10 when it comes to getting four-seamers.

Maybe that’s because of the pitchers they’ve faced. As McCann pointed out, there’s just as many pitchers going one direction as there are in another. “I think baseball changes every couple of years and everyone’s into four-seamers up and curveballs down and pitching north south instead of east west,” he pointed out before admitting: “But I also think it’s up to your staff, the staff you have.”

So maybe we can’t say a grand arching thing about all of baseball here. Sure, in some ways the sport is getting bendier — Peacock’s transformation, in particular, is an example of that. Lance McCullers and Luke Gregerson are also among the bendier pitchers in baseball. Mike Fiers is another case. Over the first month of the season, he recorded a 5.64 ERA; in eight starts since May 14, he’s produced a 2.64 mark. That date isn’t arbitrary: it’s the day on which Fiers began integrating a sinker into his fastball mix.

And then there’s the other side of the ball. If the Astros were a team full of golfers who had problems with the high pitch (like the Twins, maybe?), they might lead baseball in four-seamers seen instead of seeing the fewest of all time.

We hoped you liked reading The Astros’ Grand Fastball Experiment by Eno Sarris!

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With a phone full of pictures of pitchers' fingers, strange beers, and his two toddler sons, Eno Sarris can be found at the ballpark or a brewery most days. Read him here, writing about the A's or Giants at The Athletic, or about beer at October. Follow him on Twitter @enosarris if you can handle the sandwiches and inanity.

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sadtrombone
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sadtrombone

So the Astros are going away from four-seam fastballs, while the Rockies are emphasizing it? What is the Rockies percentage? (can’t find it on the graph).