It’s fair to say that Josiah Gray did not take the MLB by storm. A consensus top 100 prospect before the 2021 season, Gray debuted with the Dodgers that summer, shortly before being traded to the Nationals in the deal that sent Max Scherzer and Trea Turner to the Valley. He instantly became a mainstay in the Nats’ rotation.
Much like the team he joined in the summer of 2021, Gray struggled mightily over the subsequent season and a half. He finished his rookie campaign with a 5.48 ERA, 6.02 FIP, and 1.36 WHIP. His struggles were highlighted by a sky-high 2.42 HR/9. Undesirable results, to be sure, but a 24.8% K-rate, 22% hard contact rate, and 14.9% SwStr were encouraging signs heading into his sophomore campaign.
Unfortunately, Gray displayed only moderate improvement in 2022. He finished the season with a 5.02 ERA and a 5.87 FIP. He surrendered the most walks in the National League and the most home runs in the majors, thanks in part to a measly 35% groundball rate. Simply put, whatever Gray was doing was not working.
Before the 2023 season, Pitcher List’s LaMar Gibson made a compelling case for Gray to revamp his pitch mix. Gibson highlighted a reliance on a poorly located four-seam fastball as a major hindrance through the first two years of Gray’s career. He posited that a shift in focus to Gray’s more effective offerings (his curveball and slider) would yield better results.
Someone in the nation’s capital must be a regular reader of Pitcher List because Gray took the advice and changed his repertoire to great effect.
The Numbers
Gray’s 2023 results have, to date, been comparatively sublime. At the break, he’s gone 6-7 with a 3.41 ERA, earning him his first All-Star Game selection. He’s done so by waning off of his 4-seamer. After throwing the pitch at a roughly 40% clip through his first two seasons, he’s thrown it just 23% of the time in 2023. His slider is now his primary offering, thrown at a 33% clip. He’s also introduced a cutter that he throws 17% of the time and upped his sinker usage from 3% in 2022 to 11% in 2023.
Curiously, the improved results have been accompanied by a career-worst 1.44 WHIP and a drop in strikeouts. So, what’s driven the improvement? It seems obvious that simply rearranging the pitch mix has been very effective in limiting home runs and inducing ground balls.
What’s even more interesting about this development is that Gray’s slider and curveball in isolation have regressed from a year ago. Let’s dive into the repertoire and see if we can make sense of this trend.
The Slider
The slider has been Gray’s pitch of choice this year, throwing it 10% more than any other offering. He’s had great success with this pitch in the past, with hitters posting just a .237 xwOBA against it in 2022. The pitch’s 19.0% whiff rate a year ago was very strong and a 44.4% groundball rate provided much-needed relief from the longball.
In a time where it can be hard to say whether a pitcher is throwing a sweeper or a slider, no such doubt exists with Gray’s primary offering. It ranks in the 5th percentile of spin rate and only breaks about 1.7 inches horizontally. Alarming at first glance, though it could be argued that the low spin rate and unconventional movement make it hard for hitters to recognize. The lack of horizontal break almost makes the pitch look like a changeup that doesn’t break to the arm side, which might help explain the high groundball rate.
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Now, about that regression. The xwOBA has jumped to .293 and hitters are generating hard contact almost 4% more frequently than a year ago. The groundball to flyball ratio has remained relatively flat, but the whiff rate has dropped about 1.3%. With all that in mind, I don’t think there’s much to worry about here. The pitch still generates good results and the regression is likely symptomatic of the pitch becoming Gray’s primary, and therefore most expected, offering.
The Curveball
Gray threw his curveball nearly a quarter of the time in 2022 and to great effect. It generated a 33% chase rate and induced groundballs at a 47% clip, surrendering just a .187 average to opposing hitters. Most impressively, hitters produced hard contact at just a 14.9% clip against the pitch, making it Gray’s most effective offering.
Curiously, despite the exceptional results, Gray has gone away from the pitch in 2023, throwing it just 15.8% of the time. The results have been less inspiring than they were in 2022, but a .284 xwOBA and 24.6% hard contact rate are still better than league average. The lack of usage could partially be explained by questionable command over the pitch, but Gray isn’t exactly known for pinpoint accuracy.
The more likely culprit here is the cutter, which Gray introduced this year. Perhaps he developed this pitch to have a firm alternative to his unsuccessful 4-seam, but the results haven’t been much better. He’s thrown the pitch at a 17% clip despite surrendering a .381 xwOBA. I’d like to see a drop in cutter usage correspond with a rise in curveball usage.
Concerns Going Forward
As effective as Gray’s new approach was in the first half, there’s plenty of cause for concern coming out of the break. Among qualified starters, he has the second-lowest ERA-FIP mark at -1.38, trailing only Baltimore’s Tyler Wells. His xERA of 4.56 is actually worse than last year’s mark of 4.41, as is his xFIP of 4.75 versus last year’s 4.64.
Given the reduction in home runs, it may be a bit surprising that Gray’s expected numbers aren’t more aligned with his actual results. The problem is that Gray is striking out fewer batters (2.6% less, to be exact) while walking more. His 10.8% walk rate is in the bottom 10% of the league. His 83.3% LOB rate is through the roof and nearly impossible to sustain, a concerning sign for a pitcher with a 1.44 WHIP.
I’m also concerned that the pitch mix overhaul is a little bit misleading. On the surface, it’s great that he’s reduced his 4-seam usage so precipitously. However, when we add the cutter usage to the 4-seamer, it’s roughly equal to his 2022 4-seam usage. The cutter isn’t effective enough to justify this.
In the end, it seems the Nationals and Gray have only partially taken the advice of my aforementioned colleague at Pitcher List. There’s still time for this to change this year, but the first half results may provide some confirmation bias that makes it hard for them to shift the approach. Until Gray commits more fully to the soft stuff and truly backs off the fastball usage, I expect him to regress to a league-average-ish pitcher in the second half. This is a clear sell-high situation if you can make it happen.
Photo by All-Pro Reels (https://www.flickr.com/photos/joeglo/) | Adapted by Justin Paradis (@JustParaDesigns on Twitter)