Miami Marlins · Pitcher · #71
William Kempner
Age 256' 0" · 222lbBats R · Throws RDebut 2026From San Jose
ERA
2.92
W-L
1-0
K
14
WHIP
0.97
WAR
0.1
FIP
3.33
League Percentile
2026 season · percentile vs 54 qualified pitchersERA
81
2.92WHIP
93
0.97Strikeouts
0
14K/9
80
10.22Wins
0
1Bottom of leagueAverage (50)Top of league
⚠ Below the qualified innings threshold. Percentiles are for reference only.
the entire league · by ERA
Top 19%
William Kempner's ERA (2.92) ranks above average among 54 qualified pitchers. The number on each bar is a percentile (higher is better); use the tabs to change the comparison pool.
PITCHING
Season · Career| Category | Games | ERA | Wins | Losses | Saves | Innings | Strikeouts | Walks | WHIP |
|---|---|---|---|---|---|---|---|---|---|
| 2026 Season | 9 | 2.92 | 1 | 0 | 0 | 12.1 | 14 | 4 | 0.97 |
| Career | 9 | 2.92 | 1 | 0 | 0 | 12.1 | 14 | 4 | 0.97 |
Hover over a stat for its definition.
ARSENAL
Pitch arsenal · 2026 usage and average velocityFour-Seam48.2%avg 154 km/h
Sweeper22.1%avg 131 km/h
Sinker14.6%avg 151 km/h
Cutter12.6%avg 140 km/h
Changeup2.5%avg 140 km/h
ADVANCED
Advanced metrics · 2026 seasonBABIP
.241
K/9
10.22
BB/9
2.92
HR/9
0.73
Quality starts
0
Whiff%
34.1%
GAME LOG
Last 9 games · includes team result| Date | Opp | Innings | Hits | ER | Walks | Strikeouts | Team |
|---|---|---|---|---|---|---|---|
| 07.11 | vs CLE | 2.0 | 3 | 2 | 0 | 3 | L |
| 07.09 | vs SEA | 0.1 | 2 | 2 | 2 | 0 | W |
| 07.03 | @ ATH | 1.0 | 0 | 0 | 0 | 1 | W |
| 06.15 | @ PHI | 2.1 | 0 | 0 | 0 | 2 | L |
| 06.10 | vs AZ | 2.0 | 0 | 0 | 2 | 3 | W |
| 06.05 | vs TB | 1.1 | 1 | 0 | 0 | 1 | L |
| 05.31 | @ NYM | 1.1 | 2 | 0 | 0 | 3 | L |
| 05.30 | @ NYM | 1.0 | 0 | 0 | 0 | 0 | L |
| 05.05 | vs BAL | 1.0 | 0 | 0 | 0 | 1 | L |
SPLITS
Situational splits (2026)Home
Opp AVG.240
IP6.2
K8
WHIP1.50
Away
Opp AVG.105
IP5.2
K6
WHIP0.35
vs LHP
Opp AVG.167
IP8.2
K12
WHIP0.81
vs RHP
Opp AVG.214
IP3.2
K2
WHIP1.36
RISP
Opp AVG.111
IP2.2
K5
WHIP0.38
YEAR BY YEAR
Year-by-year · Career trends| Year | Team | Games | ERA | Wins | Losses | Saves | Innings | Strikeouts | Walks | WHIP |
|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | MIA | 9 | 2.92 | 1 | 0 | 0 | 12.1 | 14 | 4 | 0.97 |
