Who Does Zac Gallen Remind You of?

2019 has seen the arrival of numerous high-grade prospects — including the obvious juniors of Vlad and Fernando Tatis, as well as Nick Senzel, Austin Riley, et al, and more prized pieces of the way. Zac Gallen is name you probably hadn’t heard too much of until this year, other than he was one of the central pieces in the Marcell Ozuna trade last offseason. After going 9-1 over 91.1 IP with a 1.77 ERA in the Pacific Coast League (Triple-A) in 2019, he finally got called up for his Marlins debut.

Starting in St. Louis against the Cardinals, the team that originally drafted him, he managed to hold them to just one run on five hits, scattering two walks and six strikeouts through his five innings pitched. It wasn’t the most efficient start, as he needed 99 pitches to get through five frames of action, but for a 23-year old making his MLB debut, it was a good line.

We’ll get back to his debut, but let’s focus on his dominance at Triple-A. In addition to the 9-1 record and that gaudy 1.77 ERA, Gallen also amassed an impressive K:BB ratio of 112:17. Needless to say, he put up a ridiculous start to his season, which is saying something considering the state of the PCL this year, but his deeper analytical numbers, which we’ll get to in a moment, are also off the charts. Amidst Gallen’s great run to begin 2019, he also created a profile very similar to that of a very-well-known, extremely successful MLB pitcher. Before I reveal who it is, let’s look at the numbers and how they compare. To understand the similarities, lets first take a look at the context for each, and see how their body of work for 2019 has shaped up thus far (through the 21st of June):

Gallen (Triple-A) | 14 GS, 9-1, 91.1 IP, 333 TBF

Player A (MLB) | 16 GS, 9-3, 107.2 IP, 409 TBF

Player A has started two more games than Gallen, which has amounted to just over 16 more innings. This lines up just about perfect with the difference in games started. Gallen’s lower number of total batters faced is to be expected, considering MLB talent is broadly more difficult to get out than Triple-A talent, even in the hyper-offensive PCL this year. They also have a similar W-L record, although we all know that’s almost as team-driven as it is the cause of the pitcher. So they have both pitched a similar body of work and generally faced a similar amount of batters. Knowing said body of works, let us first look at their abilities to get people out at the plate, instead of relying on the defense to make an out, and how that compares to how often they let hitters successfully reach base:

Gallen | 112 K, 17 BB, 11.04 K/9, 1.68 BB/9, 0.71 WHIP, 0.99 HR/9

Player A | 133 K, 20 BB, 11.12 K/9, 1.67 BB/9, 0.74 WHIP, 1.67 HR/9

Very similar numbers for the most part, as both are collecting plenty of strikeouts while being quite stingy with walks and hits. The glaring difference is the home run rate, but that is an interesting situation, as Player A has given up quite a few dingers this year, but many of them have been solo shots of little consequence or in low-leverage situations, and they haven’t hurt him as much as one would expect. We’ll talk about this more after we look at the next set of numbers, which shows what has happened when hitters have made contact and/or got on base:

Gallen | .197 BABIP, .152 AVG against, 86.5% LOB%, 13.5% HR/FB

Player A | .172 BABIP, .156 AVG against, 92.9% LOB% 16.8% HR/FB

Much like the previous set, the one big discrepancy here is the homer rate, which is again a result of Player A being an anomalous outlier when it comes to giving up home runs. Beyond that HR/FB rate, Player A has actually been even better at preventing successful contact. While Gallen has been just a bit better at striking people out (33.6% K% to Player A’s 32.5%), Player A has done a better job of inducing outs instead of hits once that contact has been made. Interestingly, both players are also carrying an extremely high LOB%, which has an influence on the next set of numbers, the triple slash scores for a pitcher:

Gallen | 1.77 ERA / 3.25 FIP / 3.47 xFIP

Player A | 2.59 ERA / 3.78 FIP / 3.47 xFIP

In both players’ cases, their FIP and xFIP are at least one run (almost two for Gallen’s xFIP) higher than their ERA. This is an interesting case, because there has been a lot of talk recently about pitchers like Justin Verlander and Hyun-jin Ryu, who are outperforming their FIP and xFIP in part because they are carrying a high LOB%. They are allowing some contact, but because they are stranding so many of those that reach base, they have become outliers in the FIP matrix. Gallen fits nicely right inside that pack of players. With super low BABIPs and this differential in the slash scores, we could also say both pitchers have been somewhat “lucky” this year, although that is quite hard to fully quantify with data.

In addition to the numbers, both pitchers have similar builds and mechanics. Gallen is listed at 6-foot-2 and 191 pounds, while Player A is taller at 6-foot-5 and checks in at 220, so they are both tall and skinny but quite strong. A look at video from both players shows a distinctly similar, repeatable windup and delivery with clean mechanics. Not only are these two players putting up very similar pitching profiles, but its coming from very similar mechanics and similar body types. They are both adept at mixing velocities, and they are control masters, challenging hitters with high heat up in the zone, and slower secondary pitches on the edges and corners down, in and away. Both collect numerous swinging strikes and strikeouts on both kinds of pitches, getting some batters to swing wildly at the high fastball, and also inducing at-times-embarrassing swings on the quality secondary offerings.

Finally, its worth noting that Gallen has done all of this in a year in which the Pacific Coast League has introduced a new baseball, which has led to a ridiculous increase in homers and offense in general throughout that league. This is important because I’m sure some of you have been thinking throughout this article that “you can’t compare Triple-A and MLB”, and that is true. The two really aren’t comparable, and just because someone does great in Triple-A doesn’t mean they will fare well in The Bigs. But the fact that Gallen has done what he has, in the 2019 PCL offensive explosion, is still very noteworthy in itself.

After looking at all of this, in case you haven’t guessed by now, Player A is none other than Verlander. The resemblances between the two are quite strong, and it makes you wonder if Verlander is maybe someone that Gallen has modeled his pitching after. Even if not, and regardless of what happens after his callup, it is interesting to see two pitchers of a similar build and with similar mechanics put up such closely comparable numbers in two different environments. For now, Gallen is still a prospect with massive potential, but he is just that — a prospect.

As for Gallen’s impressive Marlins debut on Thursday, digging deeper into it reveals a start that could have come from JV himself. Although Verlander does typically pitch a bit deeper into games, the bottom line is not out of resemblance, with a low number of hits and walks and a decent number of punchouts. Gallen did get into some trouble at times, allowing a couple of hits to Jose Martinez and a couple of walks, but much like his LOB% shows, he was able to work out of the jams and limit the damage, just like Verlander is so capable of doing. On the pitching side, he was also like Verlander in his damage done with swinging strikes; he had 10 of them overall, and five of his six strikeouts were on swinging strikes, and he also threw 18 first-pitch strikes against the 22 batters he faced.

The one big difference between him and Verlander was his pitch usage: while Verlander usually uses his fastball around 50% of the time (+/-10%) and spreads his secondary stuff fairly equally across the remaining 50%, Gallen actually threw just 20 fastballs out of his 99 pitches for his first start. The rest were all secondary pitches, but they worked quite well, especially his changeup, with which he did the most damage. It will be interesting to see if and how his pitch usage will change as his MLB career continues. Certainly he is matching a similar pitching profile as Verlander, despite the difference in pitch usage, but will that usage begin trending more towards JV’s or will he continue with his own path to success? At the very least, he has earned a couple more times through the rotation, and with Jose Urena, Pablo Lopez, and Caleb Smith all still on the IL, the near future continues to look bright for Zac Gallen.