PlayerWilliam KempnerNumber#71ClubMiami Marlins · MIA · PAge25Size6' 0" · 222 lbsThrowsRHPBatsRightBornSan Jose, CAMLB debut2026-05-05 · 1st MLB seasonSchoolGonzagaContract Value$437,955/yr2026 W-L1-0
2.92
ERA
0.97
WHIP
10.2
K/9
2.9
BB/9
12.1
Innings
0
Starts
William Kempner season snapshot
Season stats
ERA
2.92
WHIP
0.97
K/9
10.2
BB/9
2.9
HR/9
0.73
IP
12.1
GS
0
W-L
1-0
William Kempner ERA trend
Earned runs per start
Avg 0.7 ER / start
↑ ERA trending up over recent starts.
William Kempner game log
| Date | Opponent | IP | H | ER | K | BB | ERA |
|---|---|---|---|---|---|---|---|
| Jul 11 | Cleveland Guardians | 2 | 3 | 2 | 3 | 0 | 9.00 |
| Jul 9 | Seattle Mariners | 0.1 | 2 | 2 | 0 | 2 | 180.00 |
| Jul 3 | Athletics | 1 | 0 | 0 | 1 | 0 | 0.00 |
| Jun 15 | Philadelphia Phillies | 2.1 | 0 | 0 | 2 | 0 | 0.00 |
| Jun 10 | Arizona Diamondbacks | 2 | 0 | 0 | 3 | 2 | 0.00 |
| Jun 5 | Tampa Bay Rays | 1.1 | 1 | 0 | 1 | 0 | 0.00 |
| May 31 | New York Mets | 1.1 | 2 | 0 | 3 | 0 | 0.00 |
| May 30 | New York Mets | 1 | 0 | 0 | 0 | 0 | 0.00 |
| May 5 | Baltimore Orioles | 1 | 0 | 0 | 1 | 0 | 0.00 |
William Kempner season splits
Home ERA
ERA0.00
Away ERA
ERA0.00
vs Left AVG
AVG0.000
vs Right AVG
AVG0.231
William Kempner monthly splits
| Month | GS | ERA | IP | K | BB | WHIP |
|---|---|---|---|---|---|---|
| May | 0 | 0.00 | 3.1 | 4 | 0 | 0.60 |
| Jun | 0 | 0.00 | 5.2 | 6 | 2 | 0.53 |
| Jul | 0 | 10.80 | 3.1 | 4 | 2 | 2.10 |
Pitch arsenal
FFFour-seam FB
48.2%95.5 mph
STSweeper
22.1%81.6 mph
SISinker
14.6%94.0 mph
FCCutter
12.6%87.3 mph
CHChangeup
2.5%86.8 mph
Performance vs teams
TeamERAGS
Hot / Cold zones
AVG by zone
- Zone 01: .600
- Zone 02: .333
- Zone 03: .333
- Zone 04: .000
- Zone 05: .000
- Zone 06: .000
- Zone 07: .000
- Zone 08: .250
- Zone 09: .000
- Zone 11: .000
- Zone 12: -
- Zone 13: .667
- Zone 14: .000
OPS by zone
- Zone 01: 1.400
- Zone 02: 1.667
- Zone 03: .667
- Zone 04: .000
- Zone 05: .000
- Zone 06: .000
- Zone 07: .000
- Zone 08: .500
- Zone 09: .000
- Zone 11: .182
- Zone 12: -
- Zone 13: 1.500
- Zone 14: .750
SLG by zone
- Zone 01: .800
- Zone 02: 1.333
- Zone 03: .333
- Zone 04: .000
- Zone 05: .000
- Zone 06: .000
- Zone 07: .000
- Zone 08: .250
- Zone 09: .000
- Zone 11: .000
- Zone 12: -
- Zone 13: 1.000
- Zone 14: .000
OBP by zone
- Zone 01: .600
- Zone 02: .333
- Zone 03: .333
- Zone 04: .000
- Zone 05: .000
- Zone 06: .000
- Zone 07: .000
- Zone 08: .250
- Zone 09: .000
- Zone 11: .182
- Zone 12: -
- Zone 13: .750
- Zone 14: .750
earnedRunAverage by zone
- Zone 01: -
- Zone 02: -
- Zone 03: -
- Zone 04: -
- Zone 05: -
- Zone 06: -
- Zone 07: -
- Zone 08: -
- Zone 09: -
- Zone 11: -
- Zone 12: -
- Zone 13: -
- Zone 14: -
numberOfPitches by zone
- Zone 01: 14.00
- Zone 02: 10.00
- Zone 03: 5.00
- Zone 04: 7.00
- Zone 05: 12.00
- Zone 06: 9.00
- Zone 07: 7.00
- Zone 08: 14.00
- Zone 09: 11.00
- Zone 11: 51.00
- Zone 12: 4.00
- Zone 13: 25.00
- Zone 14: 30.00
numberOfStrikes by zone
- Zone 01: 10.00
- Zone 02: 8.00
- Zone 03: 3.00
- Zone 04: 6.00
- Zone 05: 8.00
- Zone 06: 7.00
- Zone 07: 5.00
- Zone 08: 10.00
- Zone 09: 10.00
- Zone 11: 16.00
- Zone 12: -
- Zone 13: 5.00
- Zone 14: 9.00
0.4000.3000.200
0.4000.3000.200
Last 10 matchups
vs Cleveland Guardians — 2026-07-11
2ER · 2ip
→
vs Seattle Mariners — 2026-07-09
2ER · 0.1ip
→
vs Athletics — 2026-07-03
0ER · 1ip
→
vs Philadelphia Phillies — 2026-06-15
0ER · 2.1ip
→
vs Arizona Diamondbacks — 2026-06-10
0ER · 2ip
→
vs Tampa Bay Rays — 2026-06-05
0ER · 1.1ip
→
vs New York Mets — 2026-05-31
0ER · 1.1ip
→
vs New York Mets — 2026-05-30
0ER · 1ip
→
vs Baltimore Orioles — 2026-05-05
0ER · 1ip
→
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