William Kempner
Age 25
Contract Value $465,857/yr
Size 6' 0" · 222
Throws RHP
Bats Right
From San Jose, CA
1–0
W-L
2.92
ERA
0.97
WHIP
14
K
12.1
IP
0
GS
P-Score
P-Score not yet available
Stats updated Oct 1, 1:01 PM ET
Season overview
How good is he?
StatPlayerMLB AvgPercentile
Run Prevention7350STRONG
Skill6950ABOVE AVG
Workload2050POOR
Consistency5050AVERAGE
Form5050AVERAGE
Contact Management5050AVERAGE
Game log
Pitch arsenal (2026)
Usage %Velocity
- Four-seam FB48.2%95.5 mph
- Sweeper22.1%81.6 mph
- Sinker14.6%94.0 mph
- Cutter12.6%87.3 mph
- Changeup2.5%86.8 mph
Hot / cold zones (vs RHB)
.600.333.333.000.000.000.000.250.000
- Better than MLB avg
- Similar to MLB avg
- Worse than MLB avg
Splits
vs handedness
vs LHH
.575
vs RHH
.567
.008 OPS better vs RHH
Career
Frequently asked
What is William Kempner's ERA in 2026?+
2.92 across 0 starts and 12.1 innings, with a 0.97 WHIP and a 3.34 FIP.
When is his next start?+
No probable start has been announced.
What pitches does he throw?+
He throws four-seam fb (48.2% at 95.5 mph mph), sweeper (22.1% at 81.6 mph mph), sinker (14.6% at 94.0 mph mph), cutter (12.6% at 87.3 mph mph), changeup (2.5% at 86.8 mph mph).
What is his P-Score?+
P-Score is not yet available for this pitcher.
How has he pitched in his last five starts?+
Fewer than three starts are available, so a last-five comparison is not shown.