P | Boston Red Sox
Bats/Throws: R/R | 6' 3" 231 lbs | Age: 31
W L ERA G GS SV IP SO WHIP
2024 6 3 3.97 49 3 0 56.2 61 1.25
2025 1 3 4.58 28 0 0 35.1 35 1.33
2026 0 2 3.55 12 0 0 12.2 10 1.11
5 Seasons 8 8 4.09 110 3 0 127.2 123 1.29
G W-L ERA IP SO WHIP
2024 49 6-3 3.97 56.2 61 1.25
2025 28 1-3 4.58 35.1 35 1.33
2026 12 0-2 3.55 12.2 10 1.11
5 Seasons 110 8-8 4.09 127.2 123 1.29
MLB Percentile Rankings
Movement Profile (Induced Break)
?

Statcast Statistics

Season Age 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
2022 27 222 44 3 6.8 5.1 85.0 109.2 12.6 29.5 .202 .375 .316 .272 .302 25.0 18.6 6.8 3.95 2.97
2023 28 181 26 2 7.7 4.7 89.5 109.9 8.7 30.8 .219 .373 .357 .358 .309 46.2 14.0 18.6 3.86 5.59
2024 29 957 151 15 9.9 6.2 87.2 114.4 12.0 35.1 .224 .416 .300 .319 .384 31.1 25.3 11.2 3.97 4.16
2025 30 582 102 5 4.9 3.3 86.2 107.7 13.5 37.3 .233 .347 .318 .289 .333 31.4 23.0 7.9 4.58 3.43
2026 31 197 37 4 10.8 7.8 85.9 111.6 6.3 32.4 .291 .442 .268 .365 .430 29.7 19.6 7.8 3.55 5.51
Player 2139 360 29 8.1 5.3 86.7 114.4 11.7 34.4 .230 .391 .308 .313 .359 31.4 22.5 10.1
MLB 7.6 4.9 88.6 122.9 12.5 33.3 .243 .408 .316 .316 .369 37.0 22.2 8.4
! Note: All figures in this table cover the period 2015-present.

Statcast Pitch Arsenal

Kelly relies on 5 pitches.
Cutter
(44.7%) ,
Sweeper
(23.4%) ,
Sinker
(17.8%) ,
Four Seamer
(11.7%) ,
Changeup
(2.5%) ,


  •   
  •   
  •   

+ If Available Pitches Click to Video.


  •   
  •   
  •   
  •   
  •   
  •   
  •   

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 %
2022 45.5 54.5 31.8 13.6 9.1 36.4 40.9 22.7 15.9 20.5 9.1 20.5 20.5 13.6
2023 53.8 46.2 26.9 19.2 0.0 34.6 42.3 23.1 23.1 23.1 7.7 11.5 19.2 15.4
2024 47.7 52.3 24.5 20.5 7.3 38.4 39.7 21.9 25.2 17.2 5.3 13.2 22.5 16.6
2025 43.1 56.9 24.5 25.5 6.9 39.2 32.4 28.4 25.5 11.8 5.9 13.7 20.6 22.5
2026 48.6 51.4 16.2 29.7 5.4 29.7 43.2 27.0 18.9 18.9 10.8 10.8 24.3 16.2
Player 46.7 53.3 24.7 21.9 6.7 37.2 38.3 24.4 23.3 16.7 6.7 13.9 21.7 17.8
MLB 44.2 55.8 24.1 24.6 7.1 37.4 37.3 25.1 20.7 17.6 5.9 16.8 19.7 19.3
! Note: All figures in this table cover the period 2015-present.

Quality of Contact

Season Weak % Topped % Under % Flare/Burner % Solid % Barrel % Barrel/PA
2022 9.1 31.8 31.8 13.6 4.5 6.8 5.1
2023 3.8 38.5 30.8 19.2 0.0 7.7 4.7
2024 6.0 36.4 21.2 21.9 4.6 9.9 6.2
2025 7.8 31.4 28.4 21.6 5.9 4.9 3.3
2026 10.8 27.0 13.5 32.4 2.7 10.8 7.8
Player 7.2 33.6 24.4 21.7 4.4 8.1 5.3
MLB 4.0 32.4 24.9 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)
YearPitchTeamHand#MPHVertical
Drop
vs.
Comparable
Horizontal
Break
vs.
Comparable
Vertical
Break
vs. AvgHorizontal
Break
vs. Avg
2026 Sinker BOS R 35 95.9 18.8 -3.1 16.2ARM 0.2 11.1 -3.3 16.2ARM 0.7
2026 Changeup BOS R 5 83.3 39.4 3.2 18.5ARM 1.9 0.5 3.5 18.5ARM 3.8
2026 4-Seam Fastball BOS R 23 96.3 13.5 0.0 7.0ARM -0.9 16.2 0.1 7.0ARM -0.7
2026 Cutter BOS R 88 90.8 25.7 -1.1 3.7GLV 2.2 7.5 -0.7 3.7GLV 1.4
2026 Sweeper BOS R 46 81.7 39.0 0.1 17.9GLV 3.5 2.3 -1.1 17.9GLV 3.9
2025 Changeup BOS R 69 83.1 38.4 1.9 18.0ARM 2.9 1.5 2.6 18.0ARM 3.5
2025 Cutter BOS R 182 91.8 23.6 -0.2 2.3GLV 0.9 8.8 0.4 2.3GLV 0.1
2025 Sweeper BOS R 120 81.8 38.5 -0.6 17.2GLV 3.1 2.7 -1.8 17.2GLV 3.3
2025 Curveball BOS R 6 82.3 47.5 -3.0 8.6GLV 1.0 -7.2 -3.0 8.6GLV -0.4
2025 4-Seam Fastball BOS R 115 96.1 14.8 -1.0 9.5ARM 1.7 15.0 -0.8 9.5ARM 1.9
2025 Sinker BOS R 89 96.1 18.3 -3.2 16.1ARM 0.8 11.5 -4.1 16.1ARM 1.0
! Note: Years are in reverse order.

Run Values by Pitch Type

Year Pitch Type Team RV/100 Run Value Pitches % PA BA SLG wOBA Whiff% K% PutAway % xBA xSLG xwOBA Hard Hit %
2026 Cutter 0.8 1 88 44.7 20 .278 .500 .368 22.9 10.0 33.3 .396 .695 .488 43.8
2026 Sweeper 2.6 1 46 23.4 12 .167 .167 .082 30.4 25.0 15.0 .109 .165 .117 11.1
2026 Sinker 0.0 0 35 17.8 11 .333 .333 .245 6.7 9.1 12.5 .410 .459 .448 20.0
2026 4-Seam Fastball 1.5 0 23 11.7 8 .000 .000 .200 30.8 50.0 28.6 .100 .110 .266 50.0
2026 Changeup -3.6 0 5 2.5 -- -- -- 0.0 -- 0.0 -- -- -- --
2025 Cutter 2.4 4 182 31.3 54 .227 .273 .281 20.2 11.1 16.2 .252 .314 .301 26.8
2025 Sweeper -1.5 -2 120 20.7 27 .269 .423 .313 25.5 40.7 19.6 .210 .356 .258 33.3
2025 4-Seam Fastball -3.3 -4 115 19.8 31 .308 .654 .450 29.0 25.8 16.7 .207 .433 .338 44.4
2025 Sinker 1.2 1 89 15.3 23 .273 .318 .280 14.3 17.4 21.1 .286 .365 .302 27.8
2025 Changeup -1.5 -1 69 11.9 13 .308 .462 .331 32.0 38.5 16.1 .188 .280 .201 25.0
2025 Curveball 10.5 1 6 1.0 3 .000 .000 .000 25.0 33.3 25.0 .164 .185 .154 50.0
! 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

Year Pitch Type Pitches MPH Active Spin % Total Movement (In.) Spin-Based Observed Deviation
2026 Cutter 88 90.8 50 7.8 11:45 11:00 45
2026 4-Seam Fastball 23 96.3 88 17.3 1:00 12:45 15
2026 Sinker 35 95.9 88 19.8 1:15 2:00 -45
2026 Sweeper 46 81.7 61 18.9 8:15 9:00 -45
2025 Changeup 69 83.1 95 19.0 3:00 3:00 0
2025 Cutter 182 91.8 57 8.5 12:15 11:30 45
2025 4-Seam Fastball 115 96.1 94 17.5 1:15 1:15 0
2025 Sinker 89 96.1 95 19.9 1:15 2:00 -45
2025 Sweeper 118 81.8 57 18.1 8:15 9:00 -45
! Note: Years are in reverse order.
+ Show More Seasons
! Note: This table is showing data from the PITCHER perspective.
+ View Complete Spin Direction Leaderboard

Pitcher Arm Angle

! Note: Data is available from 2020 through the present.
+ View Complete Arm Angle Leaderboard

Statcast Pitching Run Value

Runs
Year Team PA Pitches Heart Shadow Chase Waste All
2022 59 222 1 1 -2 -1 -1
2023 43 181 2 2 -4 -1 -2
2024 238 957 -1 14 -8 -4 1
2025 151 582 3 1 -1 -3 -1
2026 51 197 2 1 0 -1 2
Player 542 2,139 8 19 -16 8 0
+ View Complete Pitching Run Value Leaderboard
+ Show Leverage-Based Run Value

Plate Discipline

Season Pitches Zone % Zone Swing % Zone Contact % Chase % Chase Contact % Edge % 1st Pitch Strike % Swing % Whiff % Meatball % Meatball Swing %
2022 222 53.6 68.1 87.7 20.4 61.9 36.5 64.4 45.9 17.6 9.9 72.7
2023 181 42.5 61.0 76.6 26.0 74.1 43.1 46.5 40.9 23.0 7.2 61.5
2024 957 49.2 66.9 79.0 26.7 54.6 43.6 67.8 46.5 28.1 7.4 81.7
2025 582 51.7 66.1 81.4 31.3 65.9 44.8 69.5 49.3 23.3 6.2 83.3
2026 197 46.7 59.8 89.1 30.5 56.3 50.3 39.2 44.2 23.0 6.6 92.3
Player 2,139 49.6 65.8 81.3 27.6 60.4 43.8 63.5 46.5 24.8 7.2 80.0
MLB 48.8 67.0 82.6 28.5 58.0 42.7 61.1 47.3 25.0 7.3 76.2
! Note: All figures in this table cover the period 2015-present.

Percentile Rankings

Run Value Pitching
Year Pitching Fastball Breaking Off
Speed
xERA Fastball
MPH
Fastball
Spin
Curve
Spin
Avg
EV
Chase% Whiff% K% BB% Barrel% Hard-
Hit%
GB% Extension
2022 63 29 79
2023 58 29 88
2024 48 25 87 43 38 87 30 87 25 70 70 13 12 95 77 92
2025 79 17 89
2026 65 63 67 38 18 76 28 89 55 34 34 64 24 89 72 94
+ View Complete Percentile Rankings Leaderboard

Expected Home Runs

Adjusted

Year Team Avg HR Trot Actual HR xHR HR-xHR Doubters Mostly Gone No Doubters No Doubter %
2022 22.81 2 1.5 1 3 1 0 0.0
2023 -- 0 0.9 -1 2 1 0 --
2024 24.57 10 9.5 1 2 6 5 50.0
2025 23.64 3 2.7 0 0 2 1 33.3
2026 24.09 1 1.8 -1 0 1 1 100.0
Player 24.15 16 16.4 0 7 11 7 43.8
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.
+ View Standard Expected Home Runs

Expected Home Runs by Park

Adjusted

Year HR
2022 2 2 2 0 1 2 2 1 0 1 1 2 1 1 1 1 1 1 2 1 2 3 2 3 1 1 2 2 3 1 1
2023 0 1 0 2 1 1 1 1 0 1 0 1 2 1 1 1 1 1 1 2 1 0 2 1 1 1 0 0 1 1 1
2024 10 11 8 11 9 9 11 10 9 8 8 9 12 9 8 9 8 8 11 11 11 9 11 11 10 8 9 9 11 8 8
2025 3 3 2 3 3 3 3 3 3 2 3 3 3 3 3 3 3 3 2 3 2 3 3 3 3 2 3 3 2 3 1
2026 1 2 1 2 2 2 2 2 2 2 2 2 1 2 2 2 2 1 2 2 1 2 2 2 2 1 2 2 2 1 1
Player 16 19 13 18 16 17 19 17 14 14 14 17 19 16 15 16 15 14 18 19 17 17 20 20 17 13 16 16 19 14 12
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.
+ View Standard Expected Home Runs By Park
+ View Complete Expected Home Runs Leaderboard

Year to Year Changes

2026 +/-   2025 +/-   2024 +/-   2023 +/-   2022
Results
BA .227 -.034 .261 +.053 .208 -.011 .219 -.040 .259
xBA .291 +.058 .233 +.009 .224 +.005 .219 +.017 .202
OBP .280 -.053 .333 +.030 .303 -.102 .405 +.100 .305
xOBP .355 +.047 .308 -.009 .317 -.088 .405 +.152 .253
SLG .318 -.078 .396 +.009 .387 +.012 .375 -.051 .426
xSLG .442 +.095 .347 -.069 .416 +.043 .373 -.002 .375
ISO .091 -.043 .134 -.045 .179 +.023 .156 -.011 .167
xISO .151 +.036 .115 -.077 .192 +.038 .154 -.019 .173
BABIP .257 -.073 .330 +.089 .241 -.028 .269 -.017 .286
wOBA .268 -.050 .318 +.018 .300 -.057 .357 +.041 .316
xwOBA .365 +.076 .289 -.030 .319 -.039 .358 +.086 .272
wOBAcon .294 -.083 .377 +.023 .354 +.047 .307 -.054 .361
xwOBAcon .430 +.097 .333 -.051 .384 +.075 .309 +.007 .302
BACON .278 -.072 .350 +.059 .291 +.022 .269 -.049 .318
xBACON .383 +.071 .312 -.002 .314 +.045 .269 +.020 .249
Statcast Hit Metrics
Hard Hit % 29.7 -1.7 31.4 +0.3 31.1 -15.1 46.2 +21.2 25.0
Avg Exit Velocity 85.9 -0.3 86.2 -1.0 87.2 -2.3 89.5 +4.5 85.0
Launch Angle Sweet-Spot % 32.4 -4.9 37.3 +2.2 35.1 +4.3 30.8 +1.3 29.5
Barrel % 10.8 +5.9 4.9 -5.0 9.9 +2.2 7.7 +0.9 6.8
Avg Launch Angle 6.3 -7.2 13.5 +1.5 12.0 +3.3 8.7 -3.9 12.6
Statcast Bat Tracking
Bat Speed 71.7 +0.9 70.8 +0.4 70.4 -1.3 71.7 -- --
Attack Angle +2° -3° 10° +1° -- --
Ideal Attack Angle % 51.5 +1.9 49.6 -1.3 50.9 +17.6 33.3 -- --
Attack Direction -1° +5° -3° +1° -5° -- --
Swing Path - Tilt 31° -2° 33° +1° 32° -3° 35° -- --
Swing Length 7.4 +0.3 7.1 -0.2 7.3 0.0 7.3 -- --
Statcast Pitch Metrics
Fastball Velocity 92.9 -1.2 94.1 -0.1 94.2 +0.2 94.0 -0.6 94.6
Breaking Velocity 81.7 -0.1 81.8 -0.4 82.2 -3.4 85.6 -0.1 85.7
Offspeed Velocity 83.3 +0.2 83.1 -0.5 83.6 +1.3 82.3 +0.3 82.0
Batted Ball Results
Barrels 4 -1 5 -10 15 +13 2 -1 3
Popup % 5.4 -1.5 6.9 -0.4 7.3 +7.3 0.0 -9.1 9.1
Flyball % 16.2 -8.3 24.5 0.0 24.5 -2.4 26.9 -4.9 31.8
Line Drive % 29.7 +4.2 25.5 +5.0 20.5 +1.3 19.2 +5.6 13.6
Groundball % 48.6 +5.5 43.1 -4.6 47.7 -6.1 53.8 +8.3 45.5
Pull % 29.7 -9.5 39.2 +0.8 38.4 +3.8 34.6 -1.8 36.4
Straight Away % 43.2 +10.8 32.4 -7.3 39.7 -2.6 42.3 +1.4 40.9
Opposite Field % 27.0 -1.4 28.4 +6.5 21.9 -1.2 23.1 +0.4 22.7
Weak Contact % 10.8 +3.0 7.8 +1.8 6.0 +2.2 3.8 -5.3 9.1
Pull Airball % 10.8 -2.9 13.7 +0.5 13.2 +1.7 11.5 -9.0 20.5
Topped Contact % 27.0 -4.4 31.4 -5.0 36.4 -2.1 38.5 +6.7 31.8
Under Contact % 13.5 -14.9 28.4 +7.2 21.2 -9.6 30.8 -1.0 31.8
Flare/Burner Contact % 32.4 +10.8 21.6 -0.3 21.9 +2.7 19.2 +5.6 13.6
Solid Contact % 2.7 -3.2 5.9 +1.3 4.6 +4.6 0.0 -4.5 4.5
HR/FB % 16.7 +4.7 12.0 -15.0 27.0 +27.0 0.0 -14.3 14.3
Popups 2 -5 7 -4 11 +11 0 -4 4
Flyballs 6 -19 25 -12 37 +30 7 -7 14
Line Drives 11 -15 26 -5 31 +26 5 -1 6
Groundballs 18 -26 44 -28 72 +58 14 -6 20
Plate Discipline
In Zone % 46.7 -5.0 51.7 +2.5 49.2 +6.7 42.5 -11.1 53.6
Out of Zone % 53.3 +5.0 48.3 -2.5 50.8 -6.7 57.5 +11.1 46.4
Edge % 50.3 +5.5 44.8 +1.2 43.6 +0.5 43.1 +6.6 36.5
Zone Swing % 59.8 -6.3 66.1 -0.8 66.9 +5.9 61.0 -7.1 68.1
Out of Zone Swing % 30.5 -0.8 31.3 +4.6 26.7 +0.7 26.0 +5.6 20.4
In Zone Contact % 89.1 +7.7 81.4 +2.4 79.0 +2.4 76.6 -11.1 87.7
Out of Zone Contact % 56.3 -9.6 65.9 +11.3 54.6 -19.5 74.1 +12.2 61.9
Whiff % 23.0 -0.3 23.3 -4.8 28.1 +5.1 23.0 +5.4 17.6
First Strike % 39.2 -30.3 69.5 +1.7 67.8 +21.3 46.5 -17.9 64.4
First Pitch Swing % 19.6 -15.5 35.1 +0.8 34.3 +13.4 20.9 -7.9 28.8
Swing % 44.2 -5.1 49.3 +2.8 46.5 +5.6 40.9 -5.0 45.9
Meatball Swing % 92.3 +9.0 83.3 +1.6 81.7 +20.2 61.5 -11.2 72.7
Meatball % 6.6 +0.4 6.2 -1.2 7.4 +0.2 7.2 -2.7 9.9
Zone Swing & Miss % 10.9 -7.7 18.6 -2.4 21.0 -0.3 21.3 +9.0 12.3
Out of Zone Swing & Miss % 43.8 +9.7 34.1 -11.3 45.4 +19.5 25.9 -12.2 38.1
In Zone 92 -209 301 -170 471 +394 77 -42 119
Out of Zone 105 -176 281 -205 486 +382 104 +1 103
Edge 99 -162 261 -156 417 +339 78 -3 81
In Zone Swings 55 -144 199 -116 315 +268 47 -34 81
Out of Zone Swings 32 -56 88 -42 130 +103 27 +6 21
In Zone Swing & Misses 6 -31 37 -29 66 +56 10 0 10
Out of Zone Swing & Misses 14 -16 30 -29 59 +52 7 -1 8
Basic
Pitches 197 -385 582 -375 957 +776 181 -41 222
PA 51 -101 152 -89 241 +198 43 -16 59
AB 44 -90 134 -78 212 +180 32 -22 54
Hits 10 -25 35 -9 44 +37 7 -7 14
Singles 8 -15 23 -3 26 +24 2 -7 9
Doubles 1 -8 9 +1 8 +3 5 +2 3
Triples 0 0 0 0 0 0 0 0 0
Home Runs 1 -2 3 -7 10 +10 0 -2 2
Walks 4 -8 12 -15 27 +19 8 +4 4
Strikeouts 10 -25 35 -26 61 +55 6 -5 11
K% 19.6 -3.4 23.0 -2.3 25.3 +11.3 14.0 -4.6 18.6
BB% 7.8 -0.1 7.9 -3.3 11.2 -7.4 18.6 +11.8 6.8
HBP 0 -3 3 +1 2 0 2 +2 0
Batted Balls 37 -65 102 -49 151 +125 26 -18 44
Number of Fastballs 146 -240 386 -109 495 +405 90 -15 105
Number of Offspeed 5 -64 69 -131 200 +137 63 -24 87
Number of Breaking 46 -80 126 -134 260 +232 28 -2 30
+ Toggle Viewing All Player's Year to Year Stats

Statcast Fielder Positioning

vs RHHvs LHH
YearAlignment TypePAwOBAPATotal%PATotal%
2022 Shifts 59 .316 32 4 12.5 27 22 81.5
2023 Shades 43 .357 19 0 0.0 24 7 29.2
2024 Shades 236 .294 132 13 9.8 104 51 49.0
2025 Shades 151 .318 82 6 7.3 69 36 52.2
2026 Shades 51 .268 39 7 17.9 12 0 0.0
! 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 %
2022 61 18.7 1.6% 1.6% 42 21.5 0.0% 0.0%
2023 38 16.5 10.5% 0.0% 44 20.8 0.0% 0.0%
2024 247 17.3 10.5% 0.4% 177 19.6 1.1% 2.3%
2025 131 16.6 14.5% 0.8% 108 19.2 0.9% 1.9%
2026 51 16.3 11.8% 0.0% 36 19.1 0.0% 2.8%

+ View Complete Pitch Tempo Leaderboard

Pitch Distribution