Player development / Development Tracker
Development Tracker
Keystone Development plan MLB

Paul Skenes

Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check

  1. 1
    Velocity Recover the four-seamer velocity he showed in 2025

    His four-seamer averaged 98.2 mph in 2025 and 96.8 in 2026. Pitchers his age typically hold their velocity over one season, so he is about 1.4 mph short of his own norm. The cause (health, mechanics, intent) needs a look first; velocity he has already shown is a realistic target, more isn’t. His arm angle moved from 23° in 2025 to 26° in 2026, a possible cause worth checking on video before changing anything.

    Four-seamer velocity: 96.8 mph  →  target 98.2 mph  · ≈8.5 runs/season (the rest of 9.4 runs at stake in a Stuff drop of 10 points both models agree on; the shape goal carries 0.9)

  2. 2
    Pitch shape Get the splitter back to its 2025 shape (2″ more drop)

    In 2025 it averaged 93.7 mph, 0″ IVB, +13″ HB (405 thrown); in 2026, 93.2 mph, 2″, +13″ (291). On one model the pitch lost about 12 points of Stuff since 2025 (it grades 101 in 2026), and this year’s pitches with the 2025 movement grade about 107: the shape alone is worth about 7 points. It’s a shape he has already thrown, not a new one. His arm angle moved from 23° in 2025 to 26° in 2026, a possible cause worth checking on video before changing anything.

    Splitter Stuff: 101  →  target 107  · ≈0.9 runs/season (model estimate)

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/694973
Keystone Development plan MLB

Oneil Cruz

CF· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in bat speed

    Clear declines: bat speed 77.2 mph → 75.1 mph (late 2026, MLB). Check video, medical and pitch shape before anyone sets a target.

  2. 2
    Approach Attack hittable pitches

    Takes 38% of the pitches the swing model says are worth swinging at (MLB median 29%). The Hitting Lab’s regressed swing-decision value is −0.72 per 100 pitches (2025–26 pooled; about −0.35 runs), past its −0.55 line, and the cause is passivity, not chasing (worse than 97% of MLB regulars on hittable pitches taken, 2025–26). With no plan a take rate like his drifts toward the median on its own (about 36% next year); the target beats that.

    Hittable-pitch take rate: 38%  →  target 34%  · no plan ≈ 36%  · ≈6.3 runs/season (what his swing decisions cost a season vs. an average hitter at his 2027 plate appearances, on the Hitting Lab’s regressed value)

    Check at the end of the 2027 season (noise then ±2%).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/665833
Keystone Development plan MLB · Triple-A · Bradenton

Konnor Griffin

SS· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Approach Swing less at pitches out of the zone

    Chases 38% of pitches out of the zone in 2026 (87th percentile for chasing). The Hitting Lab’s regressed swing-decision value is −0.88 per 100 pitches (2025–26 pooled; about −0.43 runs), past its −0.55 line, and chasing is the weak part (worse than 87% of MLB regulars, 2025–26). With no plan a chase rate like his drifts toward the median on its own (about 37% next year); the target beats that, and his earlier seasons count on 2026’s league basis (the 2026 zone raised chase rates league-wide).

    Chase rate: 38%  →  target 34%  · no plan ≈ 37%  · ≈6.2 runs/season (what his swing decisions cost a season vs. an average hitter at his 2027 plate appearances, on the Hitting Lab’s regressed value)

    Check at the end of the 2027 season (noise then ±2%).

  2. 2
    Health note Medical note: check in before the winter program

    Right elbow strain (10-day IL, May 31–Jun 26, 2026). He came back and played 30 games after it, so it doesn’t hold up the rest of the plan.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/804606
Keystone Development plan MLB · Triple-A · Bradenton

Jared Jones

Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check

  1. 1
    Pitch shape Get the four-seamer back to its 2024 shape (2″ more ride)

    In 2024 it averaged 97.3 mph, 17″ IVB, +8″ HB (941 thrown); in 2026, 98.2 mph, 16″, +9″ (762). On one model the pitch lost about 6 points of Stuff since 2024 (it grades 102 in 2026), and this year’s pitches with the 2024 movement grade about 107: the shape alone is worth about 5 points. It’s a shape he has already thrown, not a new one. His arm angle moved from 45° in 2024 to 40° in 2026, a possible cause worth checking on video before changing anything.

    Four-seamer Stuff: 102  →  target 107  · ≈1.9 runs/season (model estimate)

  2. 2
    Health note Medical note: check in before the winter program

    Right elbow UCL sprain (carried over from 2025; no reason given) (60-day IL, Feb 11–May 29, 2026). He came back and played 20 games after it, so it doesn’t hold up the rest of the plan.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/683003
Keystone Development plan MLB · Triple-A

Esmerlyn Valdez

RF· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Health Medical clearance before any development work

    Left hamstring strain (10-day IL, Sep 12–Sep 28, 2026); 0 games after it. Every other goal on this plan starts after the medical staff clears him.

  2. 2
    Contact Make more contact on strikes

    Zone contact 67% (1st percentile), and his contact costs −0.23 runs per 100 swings. With no plan it tends to come back toward the median (about 71% next year); the target beats that.

    Zone contact: 67%  →  target 73%  · no plan ≈ 71%  · ≈0.8 runs/season (what his contact costs a season vs. an average hitter at his 2027 plate appearances, on the Hitting Lab’s regressed value)

    Check at the end of the 2027 season (noise then ±2%).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/699013
Keystone Development plan MLB

Ryan O'Hearn

1B in 2027 (RF in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in bat speed

    Clear declines: bat speed 71.1 mph → 70.0 mph (2025 → 2026, MLB). Check video, medical and pitch shape before anyone sets a target.

  2. 2
    Health note Medical note: check in before the winter program

    Left quad strain (10-day IL, Aug 1–Sep 11, 2026). He came back and played 13 games after it, so it doesn’t hold up the rest of the plan.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/656811
Keystone Development plan MLB

Mitch Keller

Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check

  1. 1
    Health Medical clearance before any development work

    Right arm teres major muscle injury (60-day IL, Aug 3–still open at season’s end). Every other goal on this plan starts after the medical staff clears him.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/656605
Keystone Development plan MLB · Triple-A

Braxton Ashcraft

Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check

  1. 1
    Health Medical clearance before any development work

    Right arm discomfort (15-day IL, Sep 10–Sep 28, 2026); 0 games after it. Every other goal on this plan starts after the medical staff clears him.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/677952
Keystone Development plan MLB · Triple-A

Spencer Horwitz

DH in 2027 (1B in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Bat speed Get bat speed back to his best season

    68.8 mph average (13th percentile); he averaged 69.5 in an earlier season. Only bat speed he has already shown.

    Bat speed: 68.8 mph  →  target 69.5 mph

    Check at the 2027 All-Star break (noise then ±0.2 mph).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/687462
Keystone Development plan MLB · Triple-A

Nick Gonzales

2B in 2027 (3B in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check

  1. 1
    Position Re-establish second base (the Winter Plan moves him from third base)

    Statcast outs above average at 2B: +2 in 2024, +3 in 2025, −1 in 2026. At 3B in 2026: −11. Brandon Lowe played second base in 2026 and leaves; Isaac Paredes takes third base. If Brandon Lowe accepts the qualifying offer, the plan keeps Lowe at second and Gonzales moves to the bench, so this goal waits on Lowe’s answer.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/693304
Keystone Development plan MLB · Triple-A

Bubba Chandler

Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check

  1. 1
    Health check Velocity check before the throwing program

    Finished 2026 at 97.1 mph over his last three outings vs. a 98.4 mph season baseline (−1.3 mph). In season, a drop like this came before an arm IL stint within 30 days 3.6× as often for starters (14 injuries, a strong signal). His arm angle moved −3.2° over the same outings; velocity and arm angle together came before an arm IL stint 2.3× as often (8 injuries, suggestive). Over the winter there are too few cases to tell (2 injuries in the winter test), so this is a cheap check before the throwing program, not a forecast.

    Fastball velocity: 97.1 mph  →  target 98.4 mph

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/696149
Keystone Development plan MLB · Triple-A

Jake Mangum

CF· 2027: bench · data through Sep 27, 2026 · each goal names its check

  1. 1
    Approach Swing less at pitches out of the zone

    Chases 45% of pitches out of the zone in 2026 (99th percentile for chasing). The Hitting Lab’s regressed swing-decision value is −1.42 per 100 pitches (2025–26 pooled; about −0.70 runs), past its −0.55 line, and chasing is the weak part (worse than 98% of MLB regulars, 2025–26). With no plan a chase rate like his drifts toward the median on its own (about 44% next year); the target beats that, and his earlier seasons count on 2026’s league basis (the 2026 zone raised chase rates league-wide).

    Chase rate: 45%  →  target 41%  · no plan ≈ 44%  · ≈12.9 runs/season (what his swing decisions cost a season vs. an average hitter at his 2027 plate appearances, on the Hitting Lab’s regressed value)

    Check at the end of the 2027 season (noise then ±2%).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/663968
Keystone Development plan MLB · Triple-A

Carmen Mlodzinski

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Velocity Recover the four-seamer velocity he showed in 2025

    His four-seamer averaged 96.1 mph in 2025 and 95.0 in 2026. Pitchers his age typically change +0.1 mph over one season, so he is about 1.0 mph short of his own norm. The cause (health, mechanics, intent) needs a look first; velocity he has already shown is a realistic target, more isn’t.

    Four-seamer velocity: 95.0 mph  →  target 96.1 mph  · ≈4.8 runs/season (the rest of 5.5 runs at stake in a Stuff drop of 8 points both models agree on; the shape goal carries 0.7)

  2. 2
    Pitch shape Get the sweeper back to its 2025 shape (7″ less drop and 4″ more arm-side run)

    In 2025 it averaged 84.0 mph, 5″ IVB, −8″ HB (173 thrown); in 2026, 83.5 mph, −2″, −12″ (215). On one model the pitch lost about 14 points of Stuff since 2025 (it grades 96 in 2026), and this year’s pitches with the 2025 movement grade about 103: the shape alone is worth about 8 points. It’s a shape he has already thrown, not a new one.

    Sweeper Stuff: 96  →  target 103  · ≈0.7 runs/season (model estimate)

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/669387
Keystone Development plan MLB

Luke Weaver

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in cutter velocity

    Clear declines: cutter velocity 91.5 mph → 90.6 mph (2025 → 2026, MLB). Check video, medical and pitch shape before anyone sets a target.

  2. 2
    New pitch Try a sweeper (~83 mph, 3″ IVB, −15″ HB)

    Built from his own fastball plus the median shape of 15 pitchers with his slot and velocity, it grades +8 points against his cutter on the same model (+6 to +14 across the four fits). Uncertain: a new pitch is a season-long project and may not take.

    Stuff of new pitch: 99  →  target 107  · ≈0.4 runs/season (if it takes, at 12% usage)

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/596133
Keystone Development plan MLB · Triple-A

Evan Sisk

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Command Command first: start with the sweeper

    Location 75 (2nd percentile) in 2026 with a 12.7% walk rate over 197 batters (MLB median 8.6%). His sweeper grades 80 on location and lands in the zone 35% of the time (MLB sweepers: 43%). With no plan, a walk rate like his tends to come back toward the median on its own (about 10.9% next year); the target, 9.4%, is the more ambitious of a realistic one-year step (the median, his own best season on today’s league basis, or a big one-year gain) and what a quarter of similar pitchers beat with no plan.

    Walk rate: 12.7%  →  target 9.4%  · no plan ≈ 10.9%

    No one-season check: a lean (telling this target from noise takes about 362 batters faced; 194 in 2026).

  2. 2
    Health note Medical note: check in before the winter program

    Left elbow inflammation (15-day IL, Jul 4–Aug 5, 2026). He came back and played 18 games after it, so it doesn’t hold up the rest of the plan.

  3. ✓
    Keep Keep the gain: sinker velocity (primary fastball) up

    2025 → 2026 at MLB.

    Sinker velocity (primary fastball): 90.0 mph→ 91.1 mph

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/681895
Keystone Development plan MLB · Triple-A

Jared Triolo

SS· 2027: bench · data through Sep 27, 2026 · each goal names its check

  1. 1
    Bat speed Get bat speed back to his best season

    70.3 mph average (27th percentile); he averaged 71.4 in an earlier season. Only bat speed he has already shown.

    Bat speed: 70.3 mph  →  target 71.4 mph

    Check at the 2027 All-Star break (noise then ±0.2 mph).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/669707
Keystone Development plan MLB · Triple-A

Yohan Ramírez

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Command Command first: start with the curveball

    Location 79 (3rd percentile) in 2026 with a 12.2% walk rate over 362 batters (MLB median 8.6%). His curveball grades 70 on location and lands in the zone 37% of the time (MLB curveballs: 40%). With no plan, a walk rate like his tends to come back toward the median on its own (about 10.6% next year); the target, 9.1%, is the more ambitious of a realistic one-year step (the median, his own best season on today’s league basis, or a big one-year gain) and what a quarter of similar pitchers beat with no plan.

    Walk rate: 12.2%  →  target 9.1%  · no plan ≈ 10.6%

    Check after about 411 batters faced (more than his 2026 total) (noise then ±1.6%).

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/670990
Keystone Development plan MLB · Triple-A

Isaac Mattson

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Health Medical clearance before any development work

    Right hip impingement (15-day IL, Sep 8–Sep 28, 2026); 0 games after it. Every other goal on this plan starts after the medical staff clears him.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/676755
Keystone Development plan MLB · Triple-A

Mason Montgomery

Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in Stuff

    Clear declines: Stuff 117 → 110 (2025 → 2026, MLB). Check video, medical and pitch shape before anyone sets a target.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/682254
Keystone Development plan MLB · Triple-A · Bradenton

Noah Murdock

Pitcher· 2027: call-up · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in Stuff

    Clear declines: Stuff 97 → 89 (2025 → 2026, Triple-A). Check video, medical and pitch shape before anyone sets a target.

  2. ✓
    Keep Keep the gain: cutter velocity up

    2025 → 2026 at Triple-A.

    Cutter velocity: 89.0 mph→ 90.7 mph

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/668716
Keystone Development plan MLB · Triple-A

Thomas Harrington

Pitcher· 2027: minors · data through Sep 27, 2026 · each goal names its check

  1. 1
    Diagnose Find the cause of the drop in cutter velocity

    Clear declines: cutter velocity 88.4 mph → 86.9 mph (2025 → 2026, Triple-A). Check video, medical and pitch shape before anyone sets a target.

Goals come from Keystone models. Rate targets beat regression to the mean (“no plan ≈”); velocity and shape targets come from his own history; each goal’s check is timed to when his sample can tell it from noise. keystone-baseball.com/players/802419
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