The secret weapon in the Dodgers bullpen

4.59 ERA in 2021 obscures flamethrower's value

April 2nd, 2022

The Dodgers, like the town they call home, have stars. They have a slam-dunk Hall of Famer in Clayton Kershaw; two more building strong cases in Freddie Freeman and Mookie Betts; a 20-game winner who isn’t even his own rotation’s top starter; 2021’s WAR leader; and wow, Craig Kimbrel now, too? Look, if we stopped to highlight all the Muncys and Treinens and Turnerses and Smiths and so on, we’d be here all day.

So why, then, does it seem like a 23-year-old reliever who just posted a 4.59 ERA -- when he wasn’t being optioned to Triple-A three times -- who is wildly less famous than most of his teammates, is such an important cog in the otherwise pristine Dodgers machine?

That’s because longtime closer Kenley Jansen is off to Atlanta, and it’s because Brusdar Graterol, despite that relatively unimpressive 2021, looks like he might be something really special.

Let’s start with this: Despite what that 4.59 ERA might have said, in October, against the best competition, Graterol was fantastic. In eight games against the Cardinals, Giants and Braves, he faced 33 batters. Only four reached, all on singles, one of which was a broken-bat job that might have had a little to do with Justin Turner being worried about getting impaled by what was left of Kris Bryant’s stick.

He was so good, in fact, that of the 48 pitchers who threw at least 75 pitches last October, only one of them was more effective than Graterol -- his now ex-teammate, Jansen. (wOBA is similar to on-base percentage, just adjusted to account for extra-base hits, or lack of them.)

At first glance, it might not be hard to see why, because Graterol, acquired two years ago from the Twins in the deal that sent Kenta Maeda north, throws hard. Really, really hard. Last October, every pitcher in the playoffs combined to throw 74 pitches at 100 mph or more. Graterol alone was responsible for 59 of them. (Nearly two-thirds of the pitches he threw touched triple digits.) So far as playoff flamethrowing goes, it was a borderline unprecedented performance:

Plus, some of those 100-plus mph sinkers did ridiculous things, like this:

But even in that great October performance, Graterol didn’t miss bats, striking out only seven of those 33, or 21% -- and two of those came against a pitcher, San Francisco's Logan Webb. So far in five appearances this spring, it’s been more of the same; Graterol has allowed just one hit, a single, to the 13 batters he’s faced. Again, no walks, no damage. Yet he’s also struck out only three, despite the heat.

So now you’re thinking, sure he throws hard, but he doesn’t miss bats, and he had the 4.59 ERA, and the trips to the Minors, and the relatively unimpressive career mark of 6.8 strikeouts per nine, or 18% of batters faced, and it’s all true. He’s not terribly likely to become a Josh Hader or Kimbrel type, mowing down hitters who have little chance to make contact.

The Dodgers, surely, would like to see strikeouts, because strikeouts never become walks, and they never become extra-base hits. But what we’re learning about Graterol is that while what he does might become singles, they don’t become walks or extra-base hits, either. Between this spring and last postseason, Graterol has faced 47 consecutive hitters without allowing a walk or an extra-base hit.

And that is because he’s one of the most difficult pitchers in baseball to square up, as those uncomfortable plate appearances show you, and because his sinker moves so much, so fast, that it dips back into the zone before batters even know what’s happening.

Let’s quickly dip into the math, here, into Graterol’s two seasons with the Dodgers, combining regular season and postseason to realize what’s happening.

  • Among the 454 pitchers who have had at least 300 pitches arrive without being swung at, only five have a higher called strike rate than Graterol’s 38.4%. That’s 99th percentile.
  • Among the 311 pitchers who have allowed at least 200 batted balls, only a dozen have a higher ground-ball rate than Graterol’s 58.6%. That’s 96th percentile.
  • Among the same 311 pitchers, only five have a lower barrel rate allowed than Graterol’s 3.6%. That’s 99th percentile. (What’s a barrel? It’s the perfect combo of exit velocity and launch angle, which is another way of saying Graterol almost never allows hard-hit balls in the air, which is where real damage comes from. It’s the metric Joey Votto says he wants to lead baseball in.)

The whole package is reminiscent of Cleveland’s Emmanuel Clase, who also throws a cutter north of 100 mph, avoiding walks and loud contact, but who also doesn’t pile up the absurd strikeout numbers you’d expect.

The difference, though, is that Clase had a 1.29 ERA last year, and Graterol did not. Until, of course, the playoffs. So what changed?

“One thing we understand that Kenley Jansen left behind,” said the Dodgers’ SNLA broadcast during Wednesday’s game against the Guardians, “was the instruction of his cutter to Brusdar Graterol, trying to add to his arsenal.”

True enough. Graterol returned from the Minors in September with a new weapon, a cutter that averaged 95.3 mph, fitting right into that velocity gap between the 100 mph sinker and his 88.1 mph slider. It wasn’t, by itself, a terribly effective pitch, though he threw it only 39 times in the regular season. It did at least give hitters another thing to think about.

But perhaps more important than the new pitch was what he did to his primary ones. The slider Graterol featured at the end of the season had a ton more horizontal break, up to 10 inches worth:

This is no accident at all; this is the sweeping Dodgers slider that is being seen across baseball. (Jimmy Nelson, Treinen and Walker Buehler had three of the 10 sliders with the most horizontal movement last year.)

Last December, Eno Sarris, writing at the Athletic, wrote about the “Stuff+” metric, which attempts to rate pitches not on outcomes but on “the physical properties; the movement, the spin, the velocity that usually produces the best results.” Graterol’s sinker, unsurprisingly, made the top 10 for that pitch type. But his slider was third best, behind Aaron Bummer and Treinen, just ahead of Jacob deGrom, Clase -- there he is again -- and Joe Musgrove.

When it all works in concert, you get a plate appearance like this one against Travis d’Arnaud in Game 6 of the NLCS last year. The first pitch was a 100.4 mph sinker, moving so far inside that d’Arnaud had no chance of putting in play. The second was a slider, moving the opposite way, for a called strike. And the third? Another slider, leaving d’Arnaud with a swing so non-competitive that he stood there in disbelief.

That, right there, is why the horizontal slider works; because it goes the opposite direction of his sinker, and a batter can’t possibly cover both sides of the plate against it -- especially when that slider is moving about as fast as Kershaw’s fastball. (He’s also reportedly working on a new, mystery pitch, though he won’t say what it is.)

Graterol isn’t the best Dodgers reliever; that’s Treinen. He’s not the most famous; that’s now Kimbrel. He’s not the most interesting reclamation project plucked from elsewhere; that’s Alex Vesia or Phil Bickford. He’s not the one who’s thrown the final pitch to win a World Series; that’s Daniel Hudson. He’s not the first overall pick who owns a Cy Young; that’s David Price.

But he is the 23 year old who throws triple digits like it’s absolutely nothing, and he’s on the team that might be the best around at helping pitchers figure out how to get better. You're already seeing it with the slider shape, and the new pitch(es). Graterol might not pile up saves, or strikeouts. He might not actually be a terribly valuable fantasy pitcher for that reason. But for the real-world Dodgers? Star-studded as they might be, he might end up being the crucial piece you did not expect.