2026 Stats
W-L
1-0
ERA
0.00
WHIP
0.50
K
11
SV
0
Rest-of-Season Projections
Signed a one-year contract with the Marlins in March of 2026.
Recalled from Triple-A
The Marlins recalled Kempner from Triple-A Jacksonville on Friday, Christina De Nicola of MLB.com reports.
Analysis
Kempner was sent down last month despite logging nine scoreless innings with a 10:2 K:BB in six relief appearances. The 25-year-old will likely fill a middle relief role, but his stay in the majors could be brief as the Marlins will need a spot next week for a fifth starter, expected to be Janson Junk (shin).
Kempner was sent down last month despite logging nine scoreless innings with a 10:2 K:BB in six relief appearances. The 25-year-old will likely fill a middle relief role, but his stay in the majors could be brief as the Marlins will need a spot next week for a fifth starter, expected to be Janson Junk (shin).
Pitching Stats
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2026 MLB Game Log
2026
Minor League Game Log
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Pitching Appearances Breakdown
Average Pitch Count
20
Last 10 Games
20
Last 5 Games
24
How many pitches does William Kempner generally throw?
1-10
11-20
21-30
31-40
41-50
51-60
61-70
71-80
81-90
91-100
101-110
111-120
121+
What part of the game does William Kempner generally pitch?
1st
2nd
3rd
4th
5th
6th
7th
8th
9th
Extra
% Games Reaching Innings Threshold
% Games By Number of Innings Pitched
Left/Right Pitching Splits
Since 2024
-100%
BAA vs LHP
2026
-100%
BAA vs LHP
| BAA | K | BB | H | HR | ||||
|---|---|---|---|---|---|---|---|---|
| Since 2024vs Left | .000 | 10 | 1 | 0 | 0 | |||
| Since 2024vs Right | .231 | 1 | 1 | 3 | 0 | |||
| 2026vs Left | .000 | 10 | 1 | 0 | 0 | |||
| 2026vs Right | .231 | 1 | 1 | 3 | 0 | |||
| 2025vs Left | 0 | 0 | 0 | 0 | 0 | |||
| 2025vs Right | 0 | 0 | 0 | 0 | 0 | |||
| 2024vs Left | 0 | 0 | 0 | 0 | 0 | |||
| 2024vs Right | 0 | 0 | 0 | 0 | 0 | |||
| More Splits→ | View More Split Stats | |||||||
Home/Away Pitching Splits
Since 2024
No Stats
2026
No Stats
| ERA | WHIP | IP | K/9 | BB/9 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Since 2024Home | 0.00 | 0.69 | 4.1 | 10.4 | 4.2 | ||||
| Since 2024Away | 0.00 | 0.35 | 5.2 | 9.5 | 0.0 | ||||
| 2026Home | 0.00 | 0.69 | 4.1 | 10.4 | 4.2 | ||||
| 2026Away | 0.00 | 0.35 | 5.2 | 9.5 | 0.0 | ||||
| 2025Home | 0 | 0 | 0 | 0 | 0 | ||||
| 2025Away | 0 | 0 | 0 | 0 | 0 | ||||
| 2024Home | 0 | 0 | 0 | 0 | 0 | ||||
| 2024Away | 0 | 0 | 0 | 0 | 0 | ||||
| More Splits→ | View More Split Stats | ||||||||
Stat Review
How does William Kempner compare to other relievers?
This section compares his stats with all relief pitcher seasons from the previous three seasons (minimum 30 innings)*. The bar represents the player's percentile rank. For example, if the bar is halfway across, then the player falls into the 50th percentile for that stat and it would be considered average.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
* Exit Velocity, Barrels/BBE %, Balls Hit 95+ MPH %, and Spin Rate are benchmarked against 2019 data (min 30 IP). See here for more exit velocity/barrels stats plus an explanation of current limitations with that data set.
K/BB
5.50K/9
9.9BB/9
1.8HR/9
0.0Fastball
95.3 mphERA
0.00WHIP
0.50BABIP
.149GB/FB
0.88Left On Base
100.0%Exit Velocity
79.8 mphBarrels/BBE
0.0%Spin Rate
2561 rpmBalls Hit 95+ MPH
7.9%Swinging Strike
16.4%Advanced Pitching Stats
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Defensive Stats
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Stats Vs Today's Lineup
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More Fantasy News
Returns to Triple-A
Kempner was optioned to Triple-A Jacksonville on Tuesday.
Analysis
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Nabs first big-league win
Kempner (1-0) picked up the win Wednesday, walking two and striking out three over two scoreless, no-hit innings of relief in a victory over the Diamondbacks.
Analysis
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Recalled from Triple-A
The Marlins recalled Kempner from Triple-A Jacksonville on Saturday.
Analysis
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Sent back to minors
The Marlins optioned Kempner to Triple-A Jacksonville on Wednesday, Christina De Nicola of MLB.com reports.
Analysis
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Recalled from Triple-A
The Marlins recalled Kempner from Triple-A Jacksonville on Tuesday, Christina De Nicola of MLB.com reports.
Analysis
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