Zack Kelly
Relief Pitcher · #76 · Boston Red Sox
6' 3" · 231 lbs · Age 31 · 5 yrs exp · Pro since 2022
ZK
Boston Red Sox
Relief Pitcher
#76
Rafters file
Relief Pitcher
#76
Rafters file
Zack Kelly
41/100 stock
STRIKEOUTS46
COMMAND55
RUN PREVENTION53
WORKLOAD47
DURABILITY52
Rafters Stock41/100
12-tick model+0 (Holding)
Zack Kelly checks in with a Rafters Stock score of 41/100. Strongest grades: COMMAND, RUN PREVENTION, DURABILITY. Current tape reads HOLDING for Boston Red Sox.
2026 · pitching
3.29ERA
0W
12K
Statistical Snapshot
K12
ERA3.29
WHIP1.17
2026 · pitching
| GP | GS | W | L | ERA | WHIP | IP | K | BB | SV | HLD |
|---|---|---|---|---|---|---|---|---|---|---|
| 13 | 0 | 0 | 2 | 3.29 | 1.17 | 13.2 | 12 | 6 | 0 | 3 |
Boston Red Sox · Next 3 games
- May 7vs Tampa Bay Rays
- May 8vs Tampa Bay Rays
- May 9vs Tampa Bay Rays
Career Snapshot
pitching · 2022–2026
| GP | GS | W | L | W% | WAR | ERA | WHIP | IP | K | BB | K/BB | H | R | ER | HLD | BLSV |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 111 | 3 | 8 | 8 | .500 | — | 4.06 | 1.30 | 128.2 | 125 | 57 | 2.2 | 110 | 68 | 58 | 15 | 4 |
Postseason Pitching · 2025
| GP | W% | ERA | WHIP | IP | K |
|---|---|---|---|---|---|
| 1 | .000 | 0.00 | 0.00 | 0.1 | 1 |
Opponent Batting · 2022–2026
| P | TBF | P-TBF | OBA | OOBP | OSLUG | OOPS | 2B | HR | TB | RBI | BH | SH | SF | IBB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2164 | 551 | 3.927 | .230 | .318 | .384 | .702 | 26 | 16 | 184 | 72 | 7 | 3 | 4 | 4 |
Expanded Pitching · 2022–2026
| P/S | P/I | K/9 | GB | FB | G/F | IR | IRS | WP | BK | SB | CS | RSUP |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 38.0 | 16.8 | 8.7 | 168 | 193 | 0.9 | 50 | 23 | 5 | 1 | 12 | 2 | 16.0 |
Season by Season
pitching
| Season | Team | GP | GS | W | L | W% | WAR | ERA | WHIP | IP | K | BB | K/BB | H | R | ER | SV | HLD | BLSV |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2022 | Boston Red Sox | 13 | 0 | 1 | 0 | 1.000 | 0.2 | 3.95 | 1.32 | 13.2 | 11 | 4 | 2.8 | 14 | 6 | 6 | 0 | 1 | 0 |
| 2023 | Boston Red Sox | 8 | 0 | 0 | 0 | .000 | 0.2 | 3.86 | 1.61 | 9.1 | 6 | 8 | 0.8 | 7 | 4 | 4 | 0 | 0 | 0 |
| 2024 | Boston Red Sox | 49 | 3 | 6 | 3 | .667 | 0.6 | 3.97 | 1.25 | 56.2 | 61 | 27 | 2.3 | 44 | 31 | 25 | 0 | 8 | 1 |
| 2025 | Boston Red Sox | 28 | 0 | 1 | 3 | .250 | -0.2 | 4.58 | 1.33 | 35.1 | 35 | 12 | 2.9 | 35 | 21 | 18 | 0 | 3 | 2 |
| 2026 | Boston Red Sox | 13 | 0 | 0 | 2 | .000 | 0.0 | 3.29 | 1.17 | 13.2 | 12 | 6 | 2.0 | 10 | 6 | 5 | 0 | 3 | 1 |
Postseason Pitching
| Season | Team | GP | GS | W | L | W% | WAR | ERA | WHIP | IP | K | BB | K/BB | H | R | ER | SV | HLD | BLSV |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025 | Boston Red Sox | 1 | 0 | 0 | 0 | .000 | 0.0 | 0.00 | 0.00 | 0.1 | 1 | 0 | 0.0 | 0 | 0 | 0 | 0 | 0 | 0 |
Opponent Batting
| Season | Team | P | TBF | P-TBF | OBA | OOBP | OSLUG | OOPS | 2B | 3B | HR | TB | RBI | BH | SH | SF | IBB |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2022 | Boston Red Sox | 222 | 59 | 3.763 | .259 | .305 | .426 | .731 | 3 | 0 | 2 | 23 | 9 | 0 | 0 | 1 | 0 |
| 2023 | Boston Red Sox | 181 | 43 | 4.209 | .219 | .405 | .375 | .780 | 5 | 0 | 0 | 12 | 5 | 2 | 0 | 0 | 0 |
| 2024 | Boston Red Sox | 957 | 241 | 3.971 | .208 | .303 | .387 | .690 | 8 | 0 | 10 | 82 | 32 | 2 | 0 | 0 | 3 |
| 2025 | Boston Red Sox | 582 | 152 | 3.829 | .261 | .333 | .396 | .729 | 9 | 0 | 3 | 53 | 17 | 3 | 2 | 1 | 1 |
| 2026 | Boston Red Sox | 222 | 56 | 3.964 | .213 | .291 | .298 | .589 | 1 | 0 | 1 | 14 | 0 | 0 | 1 | 2 | 0 |
Expanded Pitching
| Season | Team | P/S | P/I | K/9 | QS | CG | SHO | GSC | GB | FB | G/F | IR | IRS | WP | BK | SB | CS | RSUP |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2022 | Boston Red Sox | 0.0 | 16.2 | 7.2 | 0 | 0 | 0 | 0.0 | 20 | 24 | 0.8 | 4 | 3 | 0 | 0 | 1 | 1 | 0.0 |
| 2023 | Boston Red Sox | 0.0 | 19.4 | 5.8 | 0 | 0 | 0 | 0.0 | 14 | 12 | 1.2 | 3 | 2 | 1 | 0 | 2 | 0 | 0.0 |
| 2024 | Boston Red Sox | 38.0 | 16.9 | 9.7 | 0 | 0 | 0 | 59.0 | 72 | 79 | 0.9 | 26 | 10 | 2 | 1 | 6 | 1 | 16.0 |
| 2025 | Boston Red Sox | 0.0 | 16.5 | 8.9 | 0 | 0 | 0 | 0.0 | 44 | 58 | 0.8 | 9 | 5 | 1 | 0 | 2 | 0 | 0.0 |
| 2026 | Boston Red Sox | 0.0 | 16.2 | 7.9 | 0 | 0 | 0 | 0.0 | 16 | 12 | 1.3 | 0 | 3 | 1 | 0 | 1 | 0 | 0.0 |
Latest News
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MLB · Last synced 2026-05-07