2B | San Francisco Giants
Bats/Throws: R/R | 6' 1" 186 lbs | Age: 28
Draft: 2019 | Rd. 12, No. 369, Colorado Rockies | University of California - Irvine
W L ERA G GS SV IP SO WHIP
2025 0 0 0.00 4 0 0 4 0 1.00
1 Season 0 0 0.00 4 0 0 4 0 1.00
G W-L ERA IP SO WHIP
2025 4 0-0 0.00 4 0 1.00
1 Season 4 0-0 0.00 4 0 1.00
Player Apps
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Pitch Usage
MLB Percentile Rankings
Movement Profile (Induced Break)
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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
2025 27 42 16 1 6.3 6.3 88.9 106.2 19.5 50.0 .338 .513 .221 .366 .366 31.3 0.0 0.0 0.00 5.81
Player 42 16 1 6.3 6.3 88.9 106.2 19.5 50.0 .338 .513 .221 .366 .366 31.3 0.0 0.0
MLB 7.2 4.9 88.6 122.9 12.4 33.3 .243 .408 .315 .316 .369 37.0 22.2 8.4
! Note: All figures in this table cover the period 2015-present.

Statcast Pitch Arsenal

Koss relies on 3 pitches.
Eephus
(88.1%) ,
Fastball
(7.1%) ,
Knuckleball
(4.8%) ,


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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 %
2025 37.5 62.5 31.3 31.3 0.0 37.5 31.3 31.3 25.0 6.3 6.3 12.5 25.0 25.0
Player 37.5 62.5 31.3 31.3 0.0 37.5 31.3 31.3 25.0 6.3 6.3 12.5 25.0 25.0
MLB 44.2 55.8 24.0 24.7 7.1 37.4 37.4 25.1 20.6 17.6 5.9 16.7 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
2025 0.0 25.0 31.3 31.3 6.3 6.3 6.3
Player 0.0 25.0 31.3 31.3 6.3 6.3 6.3
MLB 4.0 32.4 24.9 24.4 5.9 7.2 4.9
! Note: All figures in this table cover the period 2015-present.

Pitch Movement

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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
2025 Knuckleball SF R 2 58.9 79.9 6.3 3.6GLV 6.7 0.4 0.6 3.6GLV 5.0
! 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 %
2025 Knuckleball -21.3 0 2 4.8 1 1.000 1.000 .900 0.0 0.0 0.0 .476 .535 .436 0.0
! 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
2025 Eephus 36 51.3 57 8.2 10:45 10:15 30
! 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
Year Team PA Pitches Heart Shadow Chase Waste All
2025 16 42 0 2 0 0 2
Player 16 42 0 2 0 0 2
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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 %
2025 42 59.5 68.0 100.0 35.3 100.0 50.0 81.3 54.8 0.0 4.8 50.0
Player 42 59.5 68.0 100.0 35.3 100.0 50.0 81.3 54.8 0.0 4.8 50.0
MLB 48.9 67.0 82.5 28.4 58.0 42.7 61.1 47.3 25.0 7.4 76.3
! 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
2025
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Expected Home Runs

Adjusted
Year Team Avg HR Trot Actual HR xHR HR-xHR Doubters Mostly Gone No Doubters No Doubter %
2025 -- 0 0.0 0 1 0 0 --
Player -- 0 0.0 0 1 0 0 --
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
Year HR
2025 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Player 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
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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Statcast Fielder Positioning

vs RHHvs LHH
YearAlignment TypePAwOBAPATotal%PATotal%
2025 Shades 16 .221 8 0 0.0 8 3 37.5
! 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 %
2025 11 11.9 100.0% 0.0% 8 11.4 100.0% 0.0%

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