Two of the most exciting young pitchers in Major League Baseball this season have been Jared Jones of the Pittsburgh Pirates and Ryan Pepiot of the Tampa Bay Rays. Jones, with his electric fastball-slider combination, has impressed in his rookie season, while Pepiot, acquired by the Rays in the Tyler Glasnow trade, has displayed significant improvements to his pitch arsenal this season.
With both pitchers set to return from the injured list soon, baseball fans and fantasy managers alike are eager to see how each pitcher will finish their respective seasons. In this article, we will break down the pitch arsenals of Jones and Pepiot and attempt to identify which pitcher will have the stronger finish to the 2024 season.
One of the most exciting young pitchers in all of Major League Baseball, Jared Jones made his major league debut this season for the Pittsburgh Pirates. In 16 games pitched this season for Pittsburgh, Jones has produced a 26.4% strikeout rate, 7.3% walk rate, and 3.56 ERA (3.76 FIP, 3.64 SIERA) over 91.0 innings pitched. With an electric pitch arsenal highlighted by a plus four-seam fastball and slider, Jones projects to be atop the Pirates rotation alongside Paul Skenes for the foreseeable future.
Jones’s pitch arsenal consists of four pitches: a four-seam fastball, a slider, a curveball, and a changeup. Jones predominately utilizes the four-seamer and slider to right-handed hitters, while mixing in the curveball and changeup with more frequency when facing left-handed hitters. Pitch models are a fan of all the pitches in Jones’s pitch arsenal, with PLV, FanGraphs’s Stuff+, and my pitch quality model agreeing that Jones possesses a high-quality arsenal.
In my opinion, the best pitch in Jones’s pitch arsenal has been his four-seam fastball, which he has utilized 49.8% of the time this season. In addition to the plus velocity that the pitch possesses, the pitch also generates 16.1 inches of induced vertical break and has an adjusted vertical approach angle of 1.6 degrees, which is ideal for generating swing-and-miss at the top of the zone due to the “rising” effect these factors generate.
Given these factors, Jones’s four-seamer has produced a 27.3% whiff rate this season. Jones’s slider is also an excellent offering, largely due to the pitch’s impressive average velocity of 88.6 mph. As a slider with a bullet/gyro shape (closer to zero inches of horizontal movement), the pitch is able to be effectively used to generate swing-and-miss to both right and left-handed hitters, and the offering has generated a 39.8% whiff rate so far this season.
An interesting phenomenon that Jones has experienced this season is that he is currently producing reverse splits, experiencing better results against left-handed hitters than right-handed hitters. Against right-handed hitters, Jones is producing a 22.0% strikeout rate, 6.0% walk rate, and 15.9% K-BB, while against left-handed hitters, he is producing a 30.7% strikeout rate, 8.5% walk rate, and 22.2% K-BB. At first glance, these reverse splits were surprising to me, as Jones does not possess an arsenal (ex. if he was solely a fastball-changeup pitcher, as changeups perform better against opposite-handed hitters) that would indicate he would perform better against left-handed hitters, however, a hypothesis emerges after analyzing his pitch usage by batter handedness.
As shown by the table above, Jones utilizes his four-seamer 49.5% of the time and his slider 42.6% of the time against right-handed hitters, which means that 92.1% of the pitches he throws to right-handed hitters are either four-seam fastballs or sliders. In my opinion, this makes Jones’s pitches easier to identify for facing right-handed hitters, minimizing his ability to generate swing-and-miss and therefore lowering his strikeout rate against right-handed hitters. Given the consistent locations in which Jones has utilized these pitches, a right-handed hitter would likely be assuming any pitch up in the zone is a four-seam fastball, while any pitch located down in the zone is a slider. Nate Schwartz wrote about this issue with Jones in an article published in June, comparing Jones’s arsenal and pitch usage to that of Spencer Strider.
Given the plus velocity and movement characteristics that both pitches possess (as evident by their pitch grades), Jones is still able to generate a considerable amount of swing-and-miss to right-handed hitters with these pitches, albeit with lower whiff rates compared to those the offerings produce against left-handed hitters.
How can Jones resolve this issue in the future and generate more strikeouts against right-handed hitters? One option would be to mix in his curveball and changeup more frequently to right-handed hitters. Jones has displayed an ability to locate his curveball in the strike zone, and perhaps he could utilize the offering more frequently in situations such as to get a called strike early in the count.
While changeups perform better against opposite-handed hitters due to the “fading” nature of the pitch, perhaps increasing its usage to hitters who struggle against off-speed could keep hitters honest on pitches towards the bottom of the zone. Another option would be to add a sinker to his pitch arsenal, which would give hitters two fastballs to prepare for instead of one. This would allow for Jones to induce more weak contact on his fastballs, as hitters would have to guess between two fastballs with different movement profiles which will result in more contact off the “sweet spot”, and could generate more swing-and-miss on the four-seam fastball when hitters incorrectly predict that a sinker is being utilized.
Overall, Jared Jones has had an excellent rookie season and projects to be atop the Pittsburgh Pirates starting rotation alongside Paul Skenes for the foreseeable future. While he could improve his production against right-handed hitters and take another step towards ace status, the plus fastball and slider he possesses in his pitch arsenal provide him with a solid foundation to continue to build upon moving forward.
Acquired from the Los Angeles Dodgers as the centrepiece in the Tyler Glasnow trade, Ryan Pepiot has had an impressive first season with the Tampa Bay Rays. In 17 games pitched for Tampa Bay this season, Pepiot has produced a 26.7% strikeout rate, 8.8% walk rate, and 3.92 ERA (3.87 FIP, 3.82 SIERA) over 87.1 innings pitched. Since making adjustments to his pitch arsenal after being acquired by Tampa Bay, Pepiot has raised his ceiling as a starting pitcher and could realize his full potential if he’s able to improve his command of his breaking pitches.
Pepiot’s pitch arsenal consists of five pitches: a four-seam fastball, a changeup, a slider, a curveball, and a cutter. Pepiot predominately utilizes the four-seamer, changeup, and slider, while mixing in the curveball on occasion to both right and left-handed hitters. Pepiot also mixes in his cutter when facing left-handed hitters. Pitch models are fans of Pepiot’s four-seam fastball, changeup, slider, and curveball, while the models give his cutter a more average grade.
In my opinion, the best pitch in Pepiot’s pitch arsenal has been his four-seam fastball, which he has utilized 51.2% of the time this season. This offering has been effective at generating whiffs this season with a 31.3% whiff rate, and the run value of 10 that the pitch has produced this season ranks among the Top 20 four-seam fastballs in all of Major League Baseball. The improved results that Pepiot has experienced this season can be attributed to the change he made to the pitch’s shape upon being acquired by the Rays over the offseason.
As shown by the pitch cards above, Pepiot was able to add over two inches to the induced vertical break of his four-seam fastball over the offseason, allowing his four-seam fastball to not only grade better in pitch quality models but also experience better results, as evident by the increased whiff rate the offering has produced (22.4% whiff rate in 2023 vs. 31.3% whiff rate in 2024).
As described by Michael Barker in an article he wrote discussing Pepiot’s changes earlier in the season, this change in shape has allowed for Pepiot’s four-seamer to become “flatter”, as evidenced by the increased adjusted vertical approach angle on the offering, which allows for the pitch to generate more swing-and-miss when utilized at the top of the strike zone.
One question I have regarding Pepiot for the remainder of the season is his command of his secondary pitches. As shown by the heat maps above, Pepiot is effective at consistently locating his four-seamer at the top of the zone and his changeup at the bottom of the zone, ideal locations for both pitches to generate swing-and-miss. As it pertains to his other secondary pitches, the locations of these offerings become a bit more varied, with the slider frequently finding its way to the top of the zone (allowing for hitters to easily identify the pitch and make contact), and the curveball and the cutter being located all over the zone.
In my opinion, Pepiot’s top priority over the offseason should be focusing on improving his command of the slider, as being able to consistently locate the pitch lower in the zone will provide him with more opportunities to generate swing-and-miss against right-handed hitters, resulting in more strikeouts.
Unlike Jones, Pepiot’s platoon splits have been balanced between right and left-handed hitters so far this season. Against right-handed hitters, Pepiot is producing a 25.0% strikeout rate, 6.7% walk rate, and 18.3% K-BB, while against left-handed hitters, he is producing a 28.2% strikeout rate, 10.6% walk rate, and 17.6% K-BB. These relatively equal platoon splits (by measure of K-BB%) make sense since Pepiot utilizes an effective changeup that he can utilize against left-handed hitters.
Pepiot is also comfortable mixing in his changeup to right-handed hitters, which allows for his gameplan to become less “predictable” (Pepiot utilizes his four-seamer and slider 80.4% of the time against right-handed hitters, compared to Jones’s 92.1%). Refining the command of his slider should help him increase his strikeout rate against right-handed hitters, and increase his strikeout rate as a whole in the future.
Overall, Ryan Pepiot has had an excellent first season with the Tampa Bay Rays. Displaying impressive improvements to the quality of his arsenal, Pepiot has met high expectations that were placed on him as the centrepiece of the Tyler Glasnow trade, and projects to be a fixture in the Rays’ rotation for the next few seasons.
Moving Forward: Jones or Pepiot?
This leads us to the main question of this article, which pitcher will have the better finish to the season? This is a question on the minds of many baseball fans and fantasy baseball players, as both pitchers are projected to make their returns from the injured list very soon. I am particularly invested in this question because I have both of these players on my roster in one league, and might only have the available roster space to keep one or the other.
In terms of results, both pitchers are very close to each other. K-BB% is a good indicator of how well a pitcher will continue to perform, especially in large sample sizes, and Jones has a slight advantage with a 19.1% K-BB compared to Pepiot’s 17.9% K-BB. ERA estimators such as FIP and SIERA also give Jones a slight advantage over Pepiot. Pitch quality models also give a slight advantage to Jones over Pepiot.
While using metrics of how well they’ve fared so far this season gives Jones an advantage over Pepiot, public projection systems available on FanGraphs tell a different story. Both Steamer and THE BAT give Pepiot an advantage in rest of season K-BB% and ERA, while THE BAT projects Jones to produce a slightly lower FIP than Pepiot. While I am not intimately familiar with how these projection systems arrive at these conclusions, I hypothesize that the shape of Pepiot and Jones’s seasons likely has a large impact on the favorable rest-of-season projections for Pepiot.
As shown by the rolling graphs above, Pepiot’s strikeout and walk rates have remained relatively constant throughout the season while Jones’s strikeout rate has gotten progressively lower and his walk rate has gotten progressively higher throughout the season. I am curious how much Jones’s “predictability” against right-handed hitters contributes to this effect, as it would make sense that hitters would progressively strikeout less once a pitcher’s game plan becomes noticeable. Since Pepiot is more willing to mix in his changeup to same-handedness hitters, it likely keeps hitters off-balance and allows him to maintain a consistent strikeout rate throughout the course of the season.
Given these factors, I am going to predict that Ryan Pepiot will have a stronger finish to the season than Jared Jones. While Jones has shown stronger results to this point of the season, the shape of Pepiot’s season, his balanced platoon splits, and the assessment of the projection systems lead me to believe that Pepiot will have a stronger finish to the season. My preference for Pepiot is also influenced by park factors, which indicates that Tropicana Field is a better environment for pitchers than PNC Park and the fact that the Rays are a better defensive team by measure of outs above average and fielding run value than the Pirates. Both Pepiot and Jones are outstanding young pitchers who should be fixtures in their team’s rotations for the foreseeable future, however, when given a choice between Pepiot and Jones for the rest of the season, I would give a slight advantage to Ryan Pepiot.
Photos by Icon Sports Wire and Adobe Stock | Adapted by Carlos Leano
Great article Adam!
Where would you sloth these two in dynasty rankings next year among SPs? Top 20? Teens?