Giovanny Gallegos is Ready for His Close-Up

There were a lot of question marks surrounding the bullpen entering 2019, particularly after such a disastrous 2018 season. To correct it, the Cardinals brass signed Andrew Miller to settle down the left side, Jordan Hicks was handed the reins to the highest leverage at-bats, Alex Reyes was added, John Brebbia’s role was expanded, and John Gant shifted from the rotation to the bullpen. All of it was to be supported by a flurry of depth acquisitions over the last few years, each of them with impressive strikeout rates.

For the most part, it has worked. Through Tuesday, the bullpen has the highest K% in the game, the fifth best K-BB%, seventh best wOBA, and 10th best xwOBA. Their 14th best xFIP isn’t great, but it’s a major improvement over 2018. Gant, Brebbia, and Hicks have worked out brilliantly thus far, while Miller has been a roller coaster and Reyes was dispatched to Memphis after just three appearances. It’s a member of the support group I want to talk about today, though. Giovanny Gallegos has emerged as a dominant force.

Through Tuesday, his K% is a whopping 41.1%. His K% is sixth amongst MLB relievers (min. 10 innings), and his K-BB% is fifth. His percentage of swinging and called strikes (CSW) is 42.0%, best in baseball. His percentage of called strikes in the strike zone (22.6%) and called strikes in any zone (24.2%) are both the best in baseball. Through his first 14 innings this year, Gallegos has made quite an impression. Yet, he’s being used in the seventh highest leverage situations out of the Cardinal bullpen (not including Reyes or Dakota Hudson’s 0.2 innings). He’s behind Mike Mayers, Tyler Webb, and- understandably- Andrew Miller, amongst others. It’s probably time for that to change.

What makes Gallegos so effective?

Gallegos has a fairly typical repertoire. He throws a fastball and a slider. Once every few weeks, you might see him throw a change-up. His velocity is fine- 94 mph average fastball, 57th percentile amongst righty relievers since 2018, and 85 mph slider (52nd percentile). There’s nothing wrong with that velocity, but it’s not the kind of queso you’d expect from a pitcher with such an eye-popping K rate.

Tunneling doesn’t explain the K rate, either. He doesn’t tunnel the pitches particularly well off of each other, either fastball-then-slider or slider-then-fastball. If it’s not velocity or tunnel-fueled deception, what else is going on?

The slider is anything but typical, residing somewhere on the pitching Venn diagram between a curveball and a typical slider. Lest you think it should be labeled a slurve (baseball’s best portmanteau), that wouldn’t do it justice. A slurve has the lateral break of a slider at the velocity of a curve, with the vertical break of a curve. That’s... not what Gallegos throws. For Gallegos, it’s the vertical and lateral break of a curve, at the velocity of a slider. It’s an odd little pitch. It has almost no horizontal break away from right-handed hitters. Sometimes, it even gets a little arm-side run:

His fastball gets great arm-side run (upper 20th percentile among righty relievers), bearing in on righties and tailing away from lefties. Frequently, he’ll use that life to get backdoor strikes, ergo all of the called strikes on befuddled hitters surprised that the pitch tailed into the strike zone.

The combination of those two pitches, and their ability to stay away from or confuse hitters, is a big part of what makes Gallegos so effective. Now we’re getting somewhere. It also helps explain a part of his success that I haven’t mentioned yet- his skill at retiring both lefties and righties equally.

Let’s address his spin rate. He gets above average spin on his fastball (2451 RPM, good for 31st out of 218 righty relievers, min. 100 pitches). For what it’s worth, his slider spin is middling to below average- 2300 RPM, 138th out of 198. His fastball spin gives him an above average, although not elite, Bauer Unit ranking (velocity divided by spin). A high Bauer Unit score means a pitcher is better equipped to work up in the zone. Sure enough, his 34.1% CSW rate on fastballs in the upper third (through Tuesday) is one of the best in the league.

The metaphorical rug that ties the room together is his command. I’ll demonstrate this using one of Statcast’s new toys- the Attack Zone grid, which you may have seen discussed by Ben Cerutti over at Birds on the Black. Here’s how it looks.

Every pitch has its own special intention, but generally speaking, it’s a good idea for a pitcher to live in the shadow zone. As you can infer from that graphic, the dotted line is the strike zone, meaning not all pitches in the shadow zone are actually in the strike zone. In a perfect world, pitchers would live in the shadow zone while also throwing pitches in the strike zone. Using Statcast, we can see which pitchers hit that sliver of the strike zone the best. We want to find pitches in both the shadow zone in the Attack Zones section and in the strike zone using the Gameday Zones section.

Running that search for 2019, minimum 150 pitches thrown, we find Gallegos throwing inside both the strike zone and the shadow zone 30.2% of the time. That’s fourth best in baseball this year. If we change the timeframe to 2018 and 2019, minimum 300 pitches, he’s best in baseball at 28.7%. In other words, Giovanny Gallegos has been painting like Pablo Picasso. The danger is that when he misses, he gives up loud contact, much like he did on Wednesday against César Hernandez. You can see it here, about 18 seconds in, if you’re willing to deal with Fox Sports Midwest’s trash camera angle. That’s why his HR rates are elevated despite dominance in the other true outcome stats.

Admittedly, we’re still dealing with some smaller sample sizes. However, the spine of all of this information is the shape, velocity, and spin of his pitches, and that info takes far less time to stabilize. Moreover, he’s been running up these same gaudy K rates without any sort of platoon split in the minors for a few years now. It’s not like it’s anything new. It’s just that he has successfully carried it to Busch Stadium.

Now we know why Gallegos has been so dominant, even without a high octane fastball or slider or good tunneling. His pitches have atypical life, his fastball has above average spin, and he puts the ball anywhere he wants. His repertoire makes him uniquely qualified to retire lefties and righties alike. Now it’s time for Mike Shildt to start using him as a high leverage weapon.