William Kempner

RHP

Team: Miami MarlinsThrows: RHeight: 6'0"Weight: 222 lbDOB: Jun 18, 2001Born: San Jose, CA, USAActive

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Games

2.92

ERA

20.0%

K-BB%

95.5 mph

FB Velo

33.7%

CSW%

Stuff+

106

+6 vs MLB 100

vL 99vR 113▲

DLoc+

-12 vs MLB 100

vL 84▼vR 91▼

Stockyard PLoc+

—

MLB season projection

Projects next-year DLoc+

Pitching+

-2 vs MLB 100

vL 102vR 102

Synergy

—

Pitch Arsenal

Click a pitch to collapse or expand details

4-Seam Fastball

49.7%|Pitching+109▲

Velocity

95.5mph

Spin

2391rpm

CSW%

38.4%

iVB / iHB

11.5" / 16.6"

Stuff+

DLoc+

Pitching+

vs L

111▲

82▼

111▲

vs R

110▲

79▼

106▲

Grade drivers

League-average 4-Seam Fastball · 100 → 111.3

Vertical approach angle

+10.0

Carry along arm slot

+7.0

Horizontal geometry

−2.2

Break across arm slot

−1.1

Velocity

+0.7

Seam-shifted wake: amount

+0.7

Everything else

−3.8

Sweeper

22.6%|Pitching+107▲

Velocity

81.7mph

Spin

2900rpm

CSW%

28.9%

iVB / iHB

5.1" / -15.9"

Stuff+

DLoc+

Pitching+

vs L

90▼

101

105▲

vs R

110▲

112▲

107▲

Grade drivers

League-average Sweeper · 100 → 97.6

Velocity

−3.6

Break across arm slot

+3.4

Horizontal geometry

−3.4

Carry along arm slot

−2.0

Vertical approach angle

+1.9

Velo gap vs fastball

+1.7

Everything else

−0.4

Sinker

13.1%|Pitching+86▼

Velocity

94mph

Spin

2252rpm

CSW%

19.2%

iVB / iHB

3.4" / 19.7"

Stuff+

DLoc+

Pitching+

vs L

60▼

89▼

vs R

64▼

85▼

Grade drivers

League-average Sinker · 100 → 94.8

Carry along arm slot

+6.6

Vertical approach angle

+6.6

Horizontal geometry

−4.9

Seam-shifted wake: amount

−3.2

Break across arm slot

−1.7

Release height

−1.3

Everything else

−7.3

Cutter

12.1%|Pitching+92▼

Velocity

87.4mph

Spin

2621rpm

CSW%

45.8%

iVB / iHB

5.5" / -1.4"

Stuff+

DLoc+

Pitching+

vs L

77▼

75▼

88▼

vs R

100

84▼

Grade drivers

League-average Cutter · 100 → 86.3

Break across arm slot

−7.2

Seam-shifted wake: amount

−6.4

Horizontal geometry

+2.2

Carry along arm slot

+2.2

Release height

−1.2

Extension

−1.0

Everything else

−2.3

Changeup

2.5%|Pitching+—

Velocity

86.8mph

Spin

1345rpm

CSW%

iVB / iHB

-3.3" / 12.3"

Stuff+

DLoc+

Pitching+

vs L

—

vs R

—

xRV (Expected Run Value): Expected runs per 100 pitches using xwOBA on batted balls (BABIP-neutral). Negative = good (runs prevented), Positive = bad (runs allowed).

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William Kempner

Pitch Arsenal

4-Seam Fastball

Sweeper

Sinker

Cutter

Changeup

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