P | Kansas City Royals
Bats/Throws: R/R | 6' 3" 210 lbs | Age: 29
Draft: 2018 | Rd. 11, No. 344, Los Angeles Dodgers | Texas A&M
W L ERA G GS SV IP SO WHIP
2024 3 0 5.21 42 0 0 46.2 39 1.52
2025 5 7 3.51 19 19 0 112.2 77 1.14
2026 4 3 4.50 10 10 0 54 34 1.24
3 Seasons 12 10 4.13 71 29 0 213.1 150 1.25
G W-L ERA IP SO WHIP
2024 42 3-0 5.21 46.2 39 1.52
2025 19 5-7 3.51 112.2 77 1.14
2026 10 4-3 4.50 54 34 1.24
3 Seasons 71 12-10 4.13 213.1 150 1.25
MLB Percentile Rankings
Movement Profile (Induced Break)
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Statcast Statistics

Season Age Team Pitches Batted
Balls
Barrels Barrel % Barrel/PA Exit
Velocity
Max EV Launch
Angle
LA Sweet-
Spot %
xBA xSLG wOBA xwOBA xwOBAcon HardHit% K% BB% ERA xERA
2024 27 797 156 6 3.8 2.8 88.1 113.5 3.6 30.8 .280 .416 .336 .332 .381 41.0 18.5 5.7 5.21 4.55
2025 28 1689 346 21 6.1 4.6 91.1 111.9 7.4 32.9 .260 .406 .280 .321 .352 48.0 16.7 6.7 3.52 4.30
2026 29 837 176 12 6.9 5.4 88.5 112.8 10.3 33.0 .262 .380 .329 .303 .330 36.9 15.2 5.4 4.50 3.86
Player 3323 678 39 5.8 4.4 89.8 113.5 7.3 32.4 .265 .402 .305 .319 .353 43.5 16.7 6.1
MLB 7.6 4.9 88.6 122.9 12.6 33.3 .244 .407 .316 .316 .368 37.1 22.2 8.4
! Note: All figures in this table cover the period 2015-present.

Statcast Pitch Arsenal

Kolek relies on 6 pitches.
Four Seamer
(28.3%) ,
Sinker
(21.7%) ,
Slider
(16.4%) ,
Cutter
(12.3%) ,
Changeup
(11.9%) ,
Sweeper
(9.3%) ,


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+ Similar Pitchers to Stephen Kolek Based on Velocity and Movement:


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Pitch Tracking



Batted Ball Profile

AIR: Fly Balls + Line Drives + Popups All Batted Balls Batted Ball Breakdown
Season GB % AIR % FB % LD % PU % Pull % Straight % Oppo % Pull GB % Straight GB % Oppo GB % Pull AIR % Straight AIR % Oppo AIR %
2024 56.4 43.6 16.7 25.6 1.3 28.2 39.1 32.7 21.8 25.0 9.6 6.4 14.1 23.1
2025 51.7 48.3 22.3 22.5 3.5 36.7 39.6 23.7 23.4 23.4 4.9 13.3 16.2 18.8
2026 46.0 54.0 22.7 24.4 6.8 38.6 40.3 21.0 22.7 17.6 5.7 15.9 22.7 15.3
Player 51.3 48.7 21.1 23.7 3.8 35.3 39.7 25.1 22.9 22.3 6.2 12.4 17.4 18.9
MLB 44.1 55.9 24.3 24.6 7.1 37.5 37.3 25.0 20.7 17.5 5.8 16.9 19.8 19.2
! Note: All figures in this table cover the period 2015-present.

Quality of Contact

Season Weak % Topped % Under % Flare/Burner % Solid % Barrel % Barrel/PA
2024 4.5 46.8 12.2 26.9 5.8 3.8 2.8
2025 2.6 37.0 19.1 26.0 8.1 6.1 4.6
2026 4.0 36.4 22.7 22.2 6.8 6.9 5.4
Player 3.4 39.1 18.4 25.2 7.2 5.8 4.4
MLB 4.1 32.2 25.0 24.4 5.9 7.6 4.9
! Note: All figures in this table cover the period 2015-present.

Pitch Movement


How this works: This section shows two different ways to evaluate pitch movement. On the left, “Total Movement” shows the real-world movement of a pitch, including the forces of gravity, which affects every pitch thrown. Since gravity requires time, and slower pitches aren't 'better' just because they have more time to move, a pitch's movement is compared to other pitches of the same pitch type, within +/- 2 MPH and +/- 0.5 feet of extension/release. On the right, Induced Movement (or IVB) is reported without gravity, and attempts to isolate movement created by the pitcher's ability to spin and manipulate the ball.
Total Movement (in inches, w/ gravity)Induced Movement (in inches, w/o gravity)
SeasonPitchTeamHand#MPHVertical
Drop
vs.
Comparable
Horizontal
Break
vs.
Comparable
Vertical
Break
vs. AvgHorizontal
Break
vs. Avg
2026 Cutter R 103 90.3 26.8 -1.5 1.9GLV 0.1 6.4 -1.6 1.9GLV -0.3
2026 Sweeper R 78 79.9 48.3 7.1 14.7GLV -0.1 -5.4 6.4 14.7GLV 1.2
2026 Slider R 137 85.6 37.5 1.4 3.2GLV -0.8 -0.4 1.8 3.2GLV -0.4
2026 Changeup R 100 87.1 33.5 0.2 12.1ARM -2.4 2.6 1.2 12.1ARM -2.1
2026 Sinker R 182 93.7 26.2 2.5 14.8ARM -0.8 5.0 2.6 14.8ARM -0.3
2026 4-Seam Fastball R 237 94.2 17.5 -2.1 6.4ARM -1.7 13.2 -2.4 6.4ARM -1.4
2025 Curveball R 1 78.6 55.5 2.5 10.5GLV -1.4 -11.0 0.8 10.5GLV 1.5
2025 Cutter R 256 90.5 25.6 -0.7 0.0GLV -1.2 7.6 -0.7 0.0GLV -2.2
2025 4-Seam Fastball R 433 94.0 18.1 -2.2 8.2ARM -0.4 12.9 -2.9 8.2ARM 0.6
2025 Sinker R 407 93.6 27.0 2.5 16.0ARM 0.2 4.4 3.0 16.0ARM 0.9
2025 Changeup R 196 87.5 36.5 3.1 13.5ARM -1.2 -0.5 4.6 13.5ARM -1.0
2025 Slider R 279 85.4 37.8 1.8 2.8GLV -2.7 -0.4 2.2 2.8GLV -1.4
2025 Sweeper R 117 82.5 40.7 2.1 14.1GLV 0.2 -0.2 1.1 14.1GLV 0.2
! Note: Seasons are in reverse order.

Run Values by Pitch Type

Season Pitch Type Team RV/100 Run Value Pitches % PA BA SLG wOBA Whiff% K% PutAway % xBA xSLG xwOBA Hard Hit %
2026 4-Seam Fastball 0.0 0 237 28.3 44 .244 .390 .342 18.6 6.8 5.1 .241 .355 .287 23.7
2026 Sinker -1.3 -2 182 21.7 64 .322 .525 .409 5.6 6.3 10.5 .275 .375 .314 47.3
2026 Slider 1.0 1 137 16.4 44 .171 .341 .249 42.9 34.1 25.0 .221 .342 .273 42.3
2026 Cutter 1.2 1 103 12.3 21 .190 .619 .245 20.8 23.8 41.7 .193 .396 .249 37.5
2026 Changeup 0.7 1 100 11.9 32 .300 .300 .297 16.0 15.6 16.7 .322 .419 .345 24.0
2026 Sweeper -2.8 -2 78 9.3 19 .333 .611 .416 9.1 10.5 11.8 .339 .457 .360 43.8
2025 4-Seam Fastball 0.6 3 433 25.6 110 .200 .389 .297 15.4 22.7 16.8 .245 .470 .350 51.4
2025 Sinker 0.8 3 407 24.1 132 .267 .310 .328 13.1 9.8 15.3 .272 .362 .327 51.5
2025 Slider -0.1 0 279 16.5 83 .237 .375 .295 21.3 18.1 15.5 .296 .400 .312 49.3
2025 Cutter 1.7 4 256 15.2 66 .276 .345 .314 19.0 13.6 24.3 .258 .424 .330 44.0
2025 Changeup 2.6 5 196 11.6 42 .049 .049 .108 24.7 26.2 21.2 .162 .244 .202 41.9
2025 Sweeper -3.5 -4 117 6.9 27 .407 .630 .446 18.4 14.8 10.8 .309 .581 .377 34.8
2025 Curveball -4.1 0 1 0.1 -- -- -- -- -- -- -- -- -- --
! Note: Years are in reverse order.
! Note: To better align with other values, positive numbers (red) are good, and negative numbers (blue) are poor.

Spin Direction

Season Pitch Type Pitches MPH Active Spin % Total Movement (In.) Spin-Based Observed Deviation
2026 Changeup 88 87.1 68 13.1 1:45 2:45 -60
2026 Cutter 103 90.3 37 6.1 12:30 11:15 75
2026 4-Seam Fastball 237 94.2 86 14.2 1:15 1:00 15
2026 Sinker 180 93.7 72 16.0 1:15 2:30 -75
2026 Slider 137 85.6 23 4.3 9:15 8:15 60
2026 Sweeper 78 79.9 68 17.3 7:30 8:00 -30
2025 Changeup 135 87.5 72 14.2 2:00 3:00 -60
2025 Cutter 256 90.5 40 6.9 1:00 12:00 60
2025 4-Seam Fastball 433 94.0 88 14.9 1:30 1:15 15
2025 Sinker 395 93.6 76 17.2 1:30 2:45 -75
2025 Slider 279 85.4 25 4.0 8:45 8:00 45
2025 Sweeper 117 82.5 45 15.4 8:00 8:45 -45
! Note: Years are in reverse order.
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! Note: This table is showing data from the PITCHER perspective.
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Pitcher Arm Angle

! Note: Data is available from 2020 through the present.
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Statcast Pitching Run Value

Runs
Season Team PA Pitches Heart Shadow Chase Waste All
2024 211 797 -2 7 -4 -3 -2
2025 460 1,689 18 10 -10 -7 11
2026 224 837 -3 10 -5 -4 -1
Player 895 3,323 12 27 -18 12 8
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Plate Discipline

Season Pitches Zone % Zone Swing % Zone Contact % Chase % Chase Contact % Edge % 1st Pitch Strike % Swing % Whiff % Meatball % Meatball Swing %
2024 797 54.1 67.5 85.2 27.9 60.8 44.5 64.9 49.3 21.1 8.3 63.6
2025 1,689 51.7 66.0 89.6 26.3 62.6 44.6 63.1 46.8 17.7 8.7 70.7
2026 837 50.4 69.4 87.7 26.7 60.4 45.5 57.1 48.3 19.8 6.7 80.4
Player 3,323 52.0 67.2 88.0 26.8 61.6 44.8 62.1 47.8 19.1 8.1 71.0
MLB 48.7 67.0 82.7 28.6 57.9 42.6 61.2 47.3 25.0 7.3 76.2
! Note: All figures in this table cover the period 2015-present.

Percentile Rankings

Run Value Pitching
Season Pitching Fastball Breaking Off
Speed
xERA Fastball
MPH
Fastball
Spin
Curve
Spin
Avg
EV
Chase% Whiff% K% BB% Barrel% Hard-
Hit%
GB% Extension
2024 35 62 13 56 23 71 42 71 39 13 14 86 96 30 94 40
2025 81 87 18 88 34 41 19 7 25 3 10 73 82 4 87 34
2026 34 34 41 63 61 43 36 53 11 10 4 93 60 62 71 26
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Expected Home Runs

Adjusted

Season Team Avg HR Trot Actual HR xHR HR-xHR Doubters Mostly Gone No Doubters No Doubter %
2024 25.87 4 4.7 -1 2 3 2 50.0
2025 24.37 9 7.9 1 4 8 3 33.3
2026 22.10 8 5.5 3 5 5 2 25.0
Player 23.88 21 18.1 3 11 16 7 33.3
Note: xHR tells how many of this pitcher's batted balls allowed would have been out of other stadiums. The "Adjusted" view here accounts for different wall heights, distances and environmental effects using Statcast Park Factor data.
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Expected Home Runs by Park

Adjusted

Season HR
2024 4 4 4 6 5 5 5 4 4 4 5 6 6 4 5 5 5 4 4 5 4 5 6 5 4 4 4 5 5 4 4
2025 9 7 8 8 8 9 7 5 9 6 10 12 8 12 9 5 7 5 5 11 5 6 12 8 6 6 8 11 6 9 8
2026 8 4 5 6 7 7 7 3 9 8 7 8 2 10 7 4 4 4 5 8 3 3 8 4 4 2 5 7 5 5 5
Player 21 15 17 20 20 21 19 12 22 18 22 26 16 26 21 14 16 13 14 24 12 14 26 17 14 12 17 23 16 18 17
Note: xHR tells how many of this pitcher's batted balls allowed would have been out of other stadiums. The "Adjusted" view here accounts for different wall heights, distances and environmental effects using Statcast Park Factor data.
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Year to Year Changes

2026 +/-   2025 +/-   2024
Results
BA .262 +.027 ↑ .235 -.068 ↓ .303
xBA .262 +.002 ↑ .260 -.020 ↓ .280
OBP .308 +.012 ↑ .296 -.056 ↓ .352
xOBP .309 -.012 ↓ .321 -.010 ↓ .331
SLG .448 +.107 ↑ .341 -.069 ↓ .410
xSLG .380 -.026 ↓ .406 -.010 ↓ .416
ISO .186 +.080 ↑ .106 -.002 ↓ .108
xISO .118 -.028 ↓ .146 +.010 ↑ .136
BABIP .280 +.016 ↑ .264 -.098 ↓ .362
wOBA .329 +.049 ↑ .280 -.056 ↓ .336
xwOBA .303 -.018 ↓ .321 -.011 ↓ .332
wOBAcon .362 +.064 ↑ .298 -.087 ↓ .385
xwOBAcon .330 -.022 ↓ .352 -.029 ↓ .381
BACON .313 +.030 ↑ .283 -.095 ↓ .378
xBACON .313 -.008 ↓ .321 -.029 ↓ .350
Statcast Hit Metrics
Hard Hit % 36.9 -11.1 ↓ 48.0 +7.0 ↑ 41.0
Avg Exit Velocity 88.5 -2.6 ↓ 91.1 +3.0 ↑ 88.1
Launch Angle Sweet-Spot % 33.0 +0.1 ↑ 32.9 +2.1 ↑ 30.8
Barrel % 6.9 +0.8 ↑ 6.1 +2.3 ↑ 3.8
Avg Launch Angle 10.3 +2.9 ↑ 7.4 +3.8 ↑ 3.6
Statcast Bat Tracking
Bat Speed 71.9 -0.1 ↓ 72.0 +1.6 ↑ 70.4
Attack Angle 8° +1° ↑ 7° +3° ↑ 4°
Ideal Attack Angle % 47.3 -0.7 ↓ 48.0 +5.7 ↑ 42.3
Attack Direction 2° -1° ↓ 3° -7° ↓ 10°
Swing Path - Tilt 33° 0° ↓ 33° +1° ↑ 32°
Swing Length 7.1 0.0 7.1 +0.2 ↑ 6.9
Statcast Pitch Metrics
Fastball Velocity 93.3 +0.3 ↑ 93.0 -1.6 ↓ 94.6
Breaking Velocity 83.5 -1.0 ↓ 84.5 -1.4 ↓ 85.9
Offspeed Velocity 87.1 -0.4 ↓ 87.5 -1.2 ↓ 88.7
Batted Ball Results
Barrels 12 -9 ↓ 21 +15 ↑ 6
Popup % 6.8 +3.3 ↑ 3.5 +2.2 ↑ 1.3
Flyball % 22.7 +0.4 ↑ 22.3 +5.6 ↑ 16.7
Line Drive % 24.4 +1.9 ↑ 22.5 -3.1 ↓ 25.6
Groundball % 46.0 -5.7 ↓ 51.7 -4.7 ↓ 56.4
Pull % 38.6 +1.9 ↑ 36.7 +8.5 ↑ 28.2
Straight Away % 40.3 +0.7 ↑ 39.6 +0.5 ↑ 39.1
Opposite Field % 21.0 -2.7 ↓ 23.7 -9.0 ↓ 32.7
Weak Contact % 4.0 +1.4 ↑ 2.6 -1.9 ↓ 4.5
Pull Airball % 15.9 +2.6 ↑ 13.3 +6.9 ↑ 6.4
Topped Contact % 36.4 -0.6 ↓ 37.0 -9.8 ↓ 46.8
Under Contact % 22.7 +3.6 ↑ 19.1 +6.9 ↑ 12.2
Flare/Burner Contact % 22.2 -3.8 ↓ 26.0 -0.9 ↓ 26.9
Solid Contact % 6.8 -1.3 ↓ 8.1 +2.3 ↑ 5.8
HR/FB % 20.0 +8.3 ↑ 11.7 -3.7 ↓ 15.4
Popups 12 0 12 +10 ↑ 2
Flyballs 40 -37 ↓ 77 +51 ↑ 26
Line Drives 43 -35 ↓ 78 +38 ↑ 40
Groundballs 81 -98 ↓ 179 +91 ↑ 88
Plate Discipline
In Zone % 50.4 -1.3 ↓ 51.7 -2.4 ↓ 54.1
Out of Zone % 49.6 +1.3 ↑ 48.3 +2.4 ↑ 45.9
Edge % 45.5 +0.9 ↑ 44.6 +0.1 ↑ 44.5
Zone Swing % 69.4 +3.4 ↑ 66.0 -1.5 ↓ 67.5
Out of Zone Swing % 26.7 +0.4 ↑ 26.3 -1.6 ↓ 27.9
In Zone Contact % 87.7 -1.9 ↓ 89.6 +4.4 ↑ 85.2
Out of Zone Contact % 60.4 -2.2 ↓ 62.6 +1.8 ↑ 60.8
Whiff % 19.8 +2.1 ↑ 17.7 -3.4 ↓ 21.1
First Strike % 57.1 -6.0 ↓ 63.1 -1.8 ↓ 64.9
First Pitch Swing % 28.6 -6.8 ↓ 35.4 +4.6 ↑ 30.8
Swing % 48.3 +1.5 ↑ 46.8 -2.5 ↓ 49.3
Meatball Swing % 80.4 +9.7 ↑ 70.7 +7.1 ↑ 63.6
Meatball % 6.7 -2.0 ↓ 8.7 +0.4 ↑ 8.3
Zone Swing & Miss % 12.3 +1.9 ↑ 10.4 -4.4 ↓ 14.8
Out of Zone Swing & Miss % 39.6 +2.2 ↑ 37.4 -1.8 ↓ 39.2
In Zone 422 -452 ↓ 874 +443 ↑ 431
Out of Zone 415 -400 ↓ 815 +449 ↑ 366
Edge 381 -372 ↓ 753 +398 ↑ 355
In Zone Swings 293 -284 ↓ 577 +286 ↑ 291
Out of Zone Swings 111 -103 ↓ 214 +112 ↑ 102
In Zone Swing & Misses 36 -24 ↓ 60 +17 ↑ 43
Out of Zone Swing & Misses 44 -36 ↓ 80 +40 ↑ 40
Basic
Pitches 837 -852 ↓ 1,689 +892 ↑ 797
PA 224 -237 ↓ 461 +250 ↑ 211
AB 210 -207 ↓ 417 +222 ↑ 195
Hits 55 -43 ↓ 98 +39 ↑ 59
Singles 34 -40 ↓ 74 +28 ↑ 46
Doubles 11 -2 ↓ 13 +4 ↑ 9
Triples 2 0 2 +2 ↑ 0
Home Runs 8 -1 ↓ 9 +5 ↑ 4
Walks 12 -19 ↓ 31 +19 ↑ 12
Strikeouts 34 -43 ↓ 77 +38 ↑ 39
K% 15.2 -1.5 ↓ 16.7 -1.8 ↓ 18.5
BB% 5.4 -1.3 ↓ 6.7 +1.0 ↑ 5.7
HBP 2 -5 ↓ 7 +4 ↑ 3
Batted Balls 176 -170 ↓ 346 +190 ↑ 156
Fastball Percent 62.4 -2.5 ↓ 64.9 -8.2 ↓ 73.1
Offspeed Percent 11.9 +0.3 ↑ 11.6 +5.0 ↑ 6.6
Breaking Percent 25.7 +2.2 ↑ 23.5 +3.3 ↑ 20.2
Number of Fastballs 522 -574 ↓ 1,096 +513 ↑ 583
Number of Offspeed 100 -96 ↓ 196 +143 ↑ 53
Number of Breaking 215 -182 ↓ 397 +236 ↑ 161
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Statcast Fielder Positioning

vs RHHvs LHH
SeasonAlignment TypePAwOBAPATotal%PATotal%
2024 Shades 207 .335 118 1 0.8 89 39 43.8
2025 Shades 459 .281 210 5 2.4 249 221 88.8
2026 Shades 224 .329 98 31 31.6 126 70 55.6
! Note: Shifts are through the 2022 season, Shaded starting from the 2023 season, Shift: three or more infielders are on the same side of second base, Shade: positioned outside of their typical responsible slices of the field.
Learn more about how positioning is defined here

Pitch Tempo

Bases EmptyRunners On Base
SeasonTeamPitchesTempoFast %Slow %PitchesTempoFast %Slow %
2024 173 14.9 52.0% 0.6% 176 18.1 8.0% 0.0%
2025 540 14.6 57.0% 0.0% 232 18.7 3.0% 0.9%
2026 226 15.2 43.8% 1.3% 144 18.3 6.3% 0.7%

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Pitch Distribution