Zac Gallen talked Pitching with David Laurila - Let's fact check it!


Back in July 2019, David Laurila of Fangraphs did an interview with Paul DeJong. I fact checked the interview. On May 15th, 2020, Laurila was back at it with former Cardinals’ prospect Zac Gallen, who was traded to the Miami Marlins in the Marcell Ozuna trade and is now an Arizona Diamondback. He threw 1,387 pitches in 80 innings over 15 games started last year for the Marlins and D’Backs and had a 2.81 ERA, 1.23 WHIP, 96 strikeouts, and 36 walks. Gallen is who I always thought would be the biggest loss in the Ozuna deal from the Cardinals’ perspective. As of now, I feel that could end up being right. We shall see. Sandy Alcantara was an All-Star last year, I believe.


In any case, to the fact check. Everything from the article will look like this:

Gallen talks about his repertoire first, saying he has a “Four-seam, changeup, curveball, and… I call it a cutter, but it’s like a hybrid cutter/slider. You could characterize it as a hard slider, I guess.”

Fact Check: Baseball Savant calls it a cutter. (Whereas my fact checks will be in our regular type face.)

Next, they have this exchange:

Laurila: No two-seamers? Gallen: Maybe one here or there. On rare occasion I’ll kind of squeeze one inside on a righty, maybe behind in the count, or to a lefty to see if I can get him to roll over. But my four-seam is a much better pitch, so I tend to stick with that. I probably throw a [two-seamer] once a game, or every couple of games.

Above, Zac Gallen got two strikeouts on two-seamers in 2019. These were from two separate games, but he got Pete Alonso looking on two separate occasions. Below, Zac Gallen allows his only ball in play on a two-seamer in 2019, and it was a "single" by Nolan Arenado. You'll see why "single" is in quotes in a moment, as Arenado completely rolls over on it like Gallen wants.

Baseball Savant again agrees with him, as he threw 15 starts and just 30 pitches that were classified as two-seam/sinkers. Let’s look at the part where he mentions, “I’ll kind of squeeze one inside on a righty, maybe behind in the count, or to a lefty to see if I can get him to roll over.”


Out of the 30 sinkers he threw, Gallen threw 14 to righties and 16 to lefties.

Gallen's sinkers/two-seamers JUST TO RIGHTIES

He really does bust them in on a righty, doesn’t he? Maybe when he said he can control the four-seam better he was right in that aspect as well! Did he throw it behind in the count?


EVEN: 0-0 (3 times), 1-1 (twice)

AHEAD: 0-1 (once), 0-2 (once), 1-2 (3 times)

BEHIND: 1-0 (once), 2-0 (3 times)


So not quite as accurate on that one.

The next quote to look at is still about fastballs, this time the four-seamer. (Bold emphasis mine.)

Laurila: How would you describe the movement on your four-seamer? Gallen: “It has good vertical movement; it kind of keeps its plane. It has good ride, or however you want to characterize it. I don’t know exactly what the spin rate is — I think it’s somewhere between 2,350 and 2,400 [rpm] — but it plays well up in the zone.” Laurila: When did you become fully aware of that? Gallen: “Probably not until the last couple of years, although it’s something I was always curious about. While I’ve never thrown overly hard, I could get away with four-seamers up at the letters; guys would swing and miss. I never understood why. I thought it was more about velo. But once I dove into the information, I kind of got an idea that it’s got good spin, good spin efficiency, and the ball tends to hop. It has that late life.”

Fact check says that he does sit at 2,370 rpm on his four-seamer, squarely in that range. That’s awesome he knew a range of 50 that he typically sits in.


This past year, his average four-seam fastball was 92.9 mph, while league average for a starting pitcher was 93.0 mph. So it’s not overly hard for sure.


As for if he gets away with it and guys swing and miss, that’s for darn sure. When you look at pitches in the 11-13, 21-23, and 31-33 zones below, the league average swing and miss rate on a 4-seamer is 34.5%. Gallen’s was 41.1% last year. League average wOBA against on those pitches was .290. Gallen’s was .229. So not only did people make worse contact (when they made it), they made significantly worse contact...

pop out, ground out, pop up

and contact less often.

41.1% whiff rate means this happened quite often.
Laurila: Would you say it’s [your curveball is] your fourth-best pitch? Gallen: “It is in terms of repeatability. But I’d also say it’s my most important pitch. I’ve noticed that having my curveball going makes turning lineups over much easier.” Laurila: Why is that? Gallen: “I feel that it makes the strike zone bigger than it is. We were talking about my fastball having carry, and being able to pitch at the top of the zone. That allows to me pitch at the bottom of the zone. I’m able to tunnel my curveball pretty well. According to the analytics, my pitches all come out of the same slot, or very close to it. I wish I could face myself, to see what that actually looks like.”

Gallen threw 109 curveballs in the shadow of the strike zone. Here is how they looked crossing the plate. Of those 109 curveballs, 66 of them (60.6%) were in the bottom third of the zone or lower. He got a significant amount of swings and misses (pink) and foul balls (green) on those, while getting some called strikes (orange) - although those came more so in the upper portions of the zone.

Gallen's curveballs on the edges of the zone

While I am unsure about how well other pitchers do this, Gallen’s pitch offerings all come from about the same slot - no more than 3.5 inch difference vertically and 2.5 inch difference horizontally. MLB baseballs have a 2⅞ - 3 inch diameter as it is, so that difference is negligible.


As for the tunneling aspect of Gallen's curve ball with his fastball; the best example I could find of him having the 4-seamer set up the curve was an early season strikeout of fellow former Cardinal Matt Adams. Cardinalsgifs helps us to see this a lot better by combining gifs of all three pitches on the left and then providing a scopic on the right with multiple colors to differentiate more easily.


Gallen threw ball one - a four-seam fastball high and away (white in the right side scopic). He then threw two more pitches that got fouled off prior to throwing another four-seam fastball up in the zone but down the middle horizontally (red in the scopic). The fifth pitch of the plate appearance is the curveball (blue on the scopic) that Adams swings and misses here.

Adams K - scopic is four-seam (white then red) and curveball last for the K (blue)

In this strikeout of Matt Adams, I would not necessarily call this "good tunneling" by Gallen. He definitely is playing his curveball off of that earlier high and away four-seamer - and even set it up with another four-seamer directly before it. However, you'll see in this second plate appearance shown, from later in the year when Gallen was a Diamondback, that he tunneled much better going curveball first and striking out Byron Buxton of the Minnesota Twins with a four-seamer. They were back to back pitches in this example.

Buxton K - scopic is four-seam (red, and last for the K) and curveball (blue)

In the scopic on the right, this time we see regular speed then a slow motion version of it. In the slow mo (on both sides, but I personally see it better in the scopic) look how long his two pitches tunnel together in order to fool the hitter. If Gallen can continue to do this rather than just have pitches play off one another, he's gonna be really good for a while.

Last one I'm going to fact check.

Laurila: How would you describe your changeup? Gallen: “It’s got good diving action, down and in to a righty. There’s nothing I do that’s really different than a lot of guys who throw changeups. It’s pretty standard in that sense. Nothing crazy. I do pronate quite a bit, but that’s not something I think about too much. For me, the feeling is sort of like I’m pinching a key at the end; I’m turning a key over. I kind of let the index finger pull the middle finger over the ring finger.” Laurila: Have you played around with the velocity, or do you pretty much just let it do what it does? Gallen: “I just let it do what it does. With the changeup, you’re either a guy who can really take speed off, or you’re a guy who has action with it. Zack Greinke is 88-89 and it just dives down. Then you’ve got guys like Kyle Hendricks, who are throwing it more like 75. I try to not toy with the speed too much. For me, the action is more important. “When I was getting back into throwing it, in 2018, there was a guy at my agency who said, ‘You can never throw your changeup too hard.’ I was like, ‘OK, let me try this.’ It was really a conviction thing, a trust kind of thing where I would throw it and let it do what it does.”

Fact check - So a few things to consider here. How hard Gallen's change up is compared to the rest of the league is one. How much "action" he has on it - movement on his change up. How his change up moves.


1) In 2019, the league average change up was 84.5 mph with a spin rate of 1,807 rpm. Zac Gallen's change up averaged 85.0 mph and 1,499 rpm. While an agent may have told him "you can never throw your change up too hard,", Gallen throws it barely above league average. I think what Gallen said is more true, that he tries "to not toy with the speed too much. For [him], the action is more important."


2) So lets look at that action. Gallen's rpms on it are wildly different than league average. They're way less - which is good on a change up. He's got a difference in rpms from his four-seam fastball of about 870. The league average pitcher throws a change up with about a 480 rpm difference. I can't be for sure that that is why his change up played so well off of the fastball last year or if it was tunneling or if it was something else. However, I can tell you this: the Cardinals pitchers who had the best wOBA against on their fastballs and change ups last year were Jordan Hicks and Dakota Hudson. Their respective differences were approximately 930 and 710. That's much closer to Gallen for both of them than league average.


3) Does it have good diving action down and in to a righty? 291 pitchers threw change ups last year. Gallen's change up had 2.1 inches more of vertical movement than league average. He had 2 less inches of horizontal movement, however. Despite his horizontal movement being less than league average, his change up still does break towards the right-handed hitters. For instance, here are all of his change ups against the Cardinals in his first start of the year in green and overlaid in pink is his average change up to right-handed hitters on the season:

Green = Gallen's change ups vs. STL in his first start. Pink = Gallen's average change to a righty in 2019

All in all, Gallen knows himself quite well, which makes him a fun interview, I am certain! Until next time, readers. Thanks for reading!

  • Thanks @cardinalsgifs for the cover art that matched last year's quite well. Love that theme we've got going. Also for the .gifs that showed Gallen using his curve and fastball together quite well against Washington and Minnesota.

  • Thanks Baseball Savant for all the information.

  • Thanks to Fangraphs' David Laurila for the inspiration and information to do these.

  • Thanks to Brooks Baseball for their information about release point.