Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check
1
VelocityRecover 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
Pitch shapeGet 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.
CF· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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
ApproachAttack 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%).
Keystone Development planMLB · Triple-A · Bradenton
Konnor Griffin
SS· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
ApproachSwing 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
Health noteMedical 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.
Keystone Development planMLB · Triple-A · Bradenton
Jared Jones
Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check
1
Pitch shapeGet 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.
Health noteMedical 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.
Keystone Development planMLB · Triple-A
Esmerlyn Valdez
RF· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
HealthMedical 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
ContactMake 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%).
Keystone Development planMLB
Ryan O'Hearn
1B in 2027 (RF in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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
Health noteMedical 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.
Keystone Development planMLB
Mitch Keller
Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check
1
HealthMedical 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.
Keystone Development planMLB · Triple-A
Braxton Ashcraft
Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check
1
HealthMedical 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.
Keystone Development planMLB · Triple-A
Spencer Horwitz
DH in 2027 (1B in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
Bat speedGet 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).
Keystone Development planMLB · Triple-A
Nick Gonzales
2B in 2027 (3B in 2026)· 2027: lineup · data through Sep 27, 2026 · each goal names its check
1
PositionRe-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.
Keystone Development planMLB · Triple-A
Bubba Chandler
Pitcher· 2027: rotation · data through Sep 27, 2026 · each goal names its check
1
Health checkVelocity 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
Keystone Development planMLB · Triple-A
Jake Mangum
CF· 2027: bench · data through Sep 27, 2026 · each goal names its check
1
ApproachSwing 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%).
Keystone Development planMLB · Triple-A
Carmen Mlodzinski
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
VelocityRecover 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
Pitch shapeGet 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.
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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
New pitchTry 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)
Keystone Development planMLB · Triple-A
Evan Sisk
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
CommandCommand 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
Health noteMedical 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.
✓
KeepKeep the gain: sinker velocity (primary fastball) up
SS· 2027: bench · data through Sep 27, 2026 · each goal names its check
1
Bat speedGet 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).
Keystone Development planMLB · Triple-A
Yohan Ramírez
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
CommandCommand 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%).
Keystone Development planMLB · Triple-A
Isaac Mattson
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
HealthMedical 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.
Keystone Development planMLB · Triple-A
Mason Montgomery
Pitcher· 2027: bullpen · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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.
Keystone Development planMLB · Triple-A · Bradenton
Noah Murdock
Pitcher· 2027: call-up · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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.
✓
KeepKeep the gain: cutter velocity up
2025 → 2026 at Triple-A.
Cutter velocity: 89.0 mph→ 90.7 mph
Keystone Development planMLB · Triple-A
Thomas Harrington
Pitcher· 2027: minors · data through Sep 27, 2026 · each goal names its check
1
DiagnoseFind 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.