A Solution for Josiah Gray

The Nationals' future may rest on their prized pitcher figuring things out. This is one possible path.

Introduction

As the headliner of the Trea Turner and Max Scherzer deal in 2021, Josiah Gray looked poised to be a great arm in the majors for years to come. He had a 1.92 ERA in 117 innings in the Division II Northeast 10 conference and a 2.41 ERA in 198 innings in the minors, giving him top-100 prospect designation on multiple respected lists. His time in the majors has not echoed that same success; a 5.48 ERA in a partial 2021 season and a 5.02 in 2022 show significant hurdles loom in his development. It takes little time to discover his most critical problem: while he has a decent .692 OPS vs. RHB in 369 PA, he had an appalling .980 OPS in 280 PA vs. LHB. Only three qualified hitters - Aaron Judge, Yordan Alvarez, and Paul Goldschmidt - averaged such a high OPS. Something clearly is wrong with his repertoire. But what is it, and can he be fixed? Luckily for Josiah and the Nats, I have looked into it and concocted a possible solution.

His Pitch Mix

The first thing to look at is the fastball, and there's plenty to see. In 2022 his fastball, thrown 40% of the time, was hit for a .479 wOBA (a measure of overall offensive output scaled to on-base pct.), which is a higher wOBA than Aaron Judge had in a season he hit 62 home runs. When hitters put the fastball into play, it has an average launch angle of 28 degrees with an EV of 91.3 mph, which is way too close to averaging a barrel per ball in play than one would like. He already had dropped its usage from 52% to 40% in the past year, but it clearly wasn't enough; despite the change, it still had the 4th worst Run-Value in the league, only behind Rockie Chad Kuhl's slider and two washed-up aces: Patrick Corbin (slider) and Madison Bumgarner (4-seamer). This means amongst all pitches thrown in the majors, Gray's fastball created the 4th most runs for opposing hitters—a dubious distinction. But upon further examination, his fastball might simply be a fall guy.

The fastball has an elite level of flatness with a vertical approach angle of .71॰ above average, a higher mark than pitchers like Zack Wheeler and Cristian Javier, two players who find great success with their fastball despite not possessing elite velocity. Gray's fastball certainly isn't elite in velocity - it sticks around 94 - but it has above-average movement from very efficient spin in both directions. For perspective, Yusei Kikuchi, who ran an ERA north of 5 last year, is the only pitcher remotely close to Josiah Gray in terms of both fastball VAA and overall performance. Joe Ryan's 92 mph fastball performs much better, despite being almost identical in every pitching metric, like VAA, other than actual usage (Ryan even uses his 60% of the time!). Josiah Gray's poor fastball may be a symptom, not a cause. And man, is it poor with an 8.61 pCRA (projected ERA using walks, strikeouts, and barrels).

He has two strong secondaries to supplement it. An 85 mph slider that's well above-average in stats like swinging strike rate, Called Strikes + Whiffs (CSW), and xWOBA, all hovering around the 80th percentile. No problems there. There's also little fuss about his curve, which turned in solid results at 83 mph following a similar framework as the slider: the same horizontal break, going into RHB instead of LHB, with 15 extra inches of drop. Then comes the problem.

His changeup is thrown exclusively against lefties, but it doesn't feel like it. Its 16.1% CSW% is in the 4th percentile with a 3.6% swinging strike rate (what? That's horrific.). It also got demolished for a .849 wOBA and .561 xWOBA, both bottom in the league and completely off the scale. There's no comparison for it. He had no command on the pitch, with a zone rate of just 26.8%, while inducing no chases outside the zone (5th percentile). The sinker doesn't do too well either, but I forgive its poor performance because of its similarities to the changeup.

The slider (purple) and curve (blue) have the same amount of horizontal break (HB; all horizontal break is induced) while having a significant difference in induced vertical break (IVB excludes the effects of gravity).

Without the changeup, Josiah Gray could only turn to his fastball and curveball against lefties reliably. His 4-seam gets crushed by lefties for a 66.7% flyball rate and a .460 xWOBA, yet he used it 44% of the time against them. His curveball, for one. It performed admirably given the circumstances; a 14.5% swinging strike rate and 38% whiff rate on 36% usage is a great foundation to build on. He should throw the curve even more, but how much can he throw it before it gets too frequent? It's a good pitch, but nothing spectacular. His slider also worked well against lefties but was a limited sample - he began to throw it more late in the year vs. them, and it deserves a more extended look in 2023. This puzzle makes him dance around the zone with his other offerings and leaves him with all his pitches having more than a 10% walk rate. Not good.

Contextualizing the Struggle

With all the pieces put together, one can understand his struggles against lefties. With arguably only the curve and the slider to use, he's given up the highest fly ball rate in the league by far to LHB, with a 65:44 K:BB ratio and 1.83 WHIP along with it. His pitches' pCRAs against lefties are above 5, and the fastball and changeup are near 8. He is terrified to throw strikes because he gets hammered, which makes him fall behind, and it all spirals out of control. Literally.

Using a new stat by the team of PitcherList, PLV, we can examine how well the pitches did based on their location, velocity, and break, rather than what happened to them after they left their hand. It's a nice change of pace from the result-oriented metrics like xWOBA, pCRA, etc. Each pitch is graded 0-10, with 5 as average. From my limited experience, any average below 4.8 is terrible, and 4.6 is horrific, and the opposite on the other end of the spectrum. Of course, the exact benchmark depends on the pitch: fastballs are hit harder than average, splitters less so, etc. Looking below, his fastball does quite well on the high end of the spectrum, but many of his fastballs also spring up in that 3-4 range. Pitching is hard, but he has a disproportionate amount of uncompetitive pitches that sometimes might induce a chase up and out of the zone for some, but not realistically for him without elite velocity or secondaries.

Every pitch being below average is problematic, especially when your changeup is at a pitiful 4.38. He needs to supplement his arsenal with something that can attack them. None of his pitches have a walk rate below 10% against lefties, which shows. 

People may think that the changeup isn't a big deal because he only throws it 5% of the time. Let me tell you the story of Blake Snell, who was getting demolished in the first half of 2021 for a 4.99 ERA in 70 innings. His changeup was thrown only around 10% of the time over that period - he rapidly dropped its usage over those four months - until August, when he dropped it entirely. His ERA during August and September? His two best, averaging below 2. What is it with changeups causing problems? In any event, Snell's repertoire is highly similar to Gray's in overall movement, albeit mirrored and not as scrunched together. Maybe Gray could learn something from the struggles of a former Cy Young winner.

Blake Snell saw great success after ditching his changeup for good in 2021 - he brought it back with a bit more success in 2022.

Blake Snell’s pitch movement chart is practically a mirror image of Gray’s, without the sinker.

A Plan for Improvement Against LHB:

All that said, here are the fixes I would propose for Gray:

Step 1: Axe the changeup like Snell. It doesn't work.

Step 2: Throw a cutter. He already throws a sinker to righties, which is the basis of a tunnel with a cutter already. Look no further than Corbin Burnes, who throws cutters to lefties over 60% of the time to the outside corner while mixing in his sinker with the same spin axis. Gray doesn't need it to be even above average with it - it just needs to be a pitch he's willing to attack lefties with. Gray's sinker is not good by any stretch, but a decent cutter paired with it is an improvement. It would slot into the small "dead zone" between the purple blob of the slider and the red/orange blob of the fastball and sinker. 

Step 3: Throw in the zone more with the fastball, while keeping it in the upper third. This seems obvious, but I suspect his pitches, especially fastball, don't perform better than they do because he can't get the fastball in the zone. Typically, pitchers will trade more fly balls for more swinging strikes by attacking the top of the zone with the heater. In Josiah Gray's case, he trades more fly balls for nothing. He has just 13 strikeouts to 25 walks on the pitch, indicating most of the time, the pitch is either a meatball or noncompetitive, costing him dearly. 

Step 4: Get better defensive luck. He doesn't control this element of the team, and they aren't the cause of his home run problem, but it may be the cause of his fear of throwing in the zone. People like to mention the Phillies' complete disregard for defense, but their -34 Outs Above Average (OAA) was only 2nd-to-last. The Nats had by far the worst at an appalling -50. Hopefully, CJ Abrams doesn't run -13 OAA in half a season at SS again. Same for Dee Strange-Gordon, who put up the same -13 in ⅕ of a season. Yikes.

My propositions for pitch mix are as follows: 

For RHB (approximate usage rate in parentheses): Slider(40)/Fastball(30)/Curve(15)/Sinker(10)/Cutter(5) - About the same as before with the new cutter in the mix.

For LHB: Curve(30)/Slider(30)/Fastball(20)/Cutter(15)/Sinker(5) - The fastball still plays, but I'm not sure it deserves heavy usage against LHB with how hard it's hit. He threw his slider more vs. LHB than his curve by the end of the year, so an even split is reasonable. The cutter and fastball dynamic depends on the type of cutter he chooses to throw and how good he is with it, so it's hard to say.

Conclusion

Despite all these adjustments that he can make, he's still getting unlucky, according to xWOBA, xFIP, and SIERA. His SIERA is a decent 4.27 compared to a league average 3.90 , and he will get plenty of innings to work things out with two great secondaries. Who else are the Nationals going to start? He plays at Nationals Park, which is hitter-friendly, but he deserves a little better than the hand he's been dealt. If all goes well, I could see his ERA go south of 4.00, but the addition of a solid cutter should keep him below 4.50 and towards league-average. I wouldn’t expect much improvement in home run rate, but a better strikeout to walk ratio should be a given. Hopefully, he can take that next step in 2023.

There's light at the end of the tunnel. Specifically, the new one that includes a cutter.