George Caster has allowed the most home runs by a relief pitcher in a game, with 6 HR against the Red Sox on September 24, 1940.
Interpreted as:
Which reliever most homers in one regular-season game ever?| NAME | HR | DATE | TM | OPP | DEC | GS | ERA | SO | CG | SHO | SV | IP | H | ER | R | BB | HBP | GF | IBB | TBF | WP | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | G. Caster | 6 | 9/24/1940 |  PHA | vs |  BSA | 0 | 34.71 | 1 | 0 | 0 | 0 | 2.1 | 10 | 9 | 9 | 1 | 0 | 0 | 17 | 0 | ||
| 2 |  | C. Anderson | 5 | 9/17/2020 |  TOR | @ |  NYY | L | 0 | 23.63 | 4 | 0 | 0 | 0 | 2.2 | 8 | 7 | 7 | 1 | 0 | 0 | 0 | 17 | 1 |
| 3 |  | D. McGowan | 5 | 6/16/2015 |  PHI | @ |  BAL | 0 | 16.20 | 4 | 0 | 0 | 0 | 3.1 | 7 | 6 | 7 | 2 | 0 | 0 | 0 | 18 | 0 | |
| 4 |  | A. Lorraine | 5 | 9/2/2002 |  MIL | @ |  CHC | 0 | 22.09 | 2 | 0 | 0 | 0 | 3.2 | 9 | 9 | 9 | 3 | 0 | 0 | 0 | 23 | 0 | |
| 5 |  | F. Pastore | 5 | 5/25/1979 |  CIN | @ |  LAD | 0 | 38.57 | 2 | 0 | 0 | 0 | 2.1 | 9 | 10 | 10 | 1 | 0 | 0 | 0 | 17 | 0 | |
| 6 |  | C. Skok | 5 | 7/30/1978 |  ATL | vs |  MON | 0 | 27.00 | 3 | 0 | 0 | 0 | 2.2 | 9 | 8 | 8 | 1 | 0 | 0 | 0 | 18 | 0 | |
| 7 |  | K. Montero | 4 | 9/20/2024 |  DET | @ | BAL | 0 | 9.64 | 7 | 0 | 0 | 0 | 4.2 | 7 | 5 | 5 | 1 | 0 | 0 | 0 | 22 | 0 | |
| 8 |  | G. Anderson | 4 | 6/11/2024 |  TEX | @ | LAD | 0 | 94.50 | 0 | 0 | 0 | 0 | 0.2 | 6 | 7 | 7 | 1 | 0 | 0 | 0 | 9 | 0 | |
| 9 |  | J. Junis | 4 | 4/29/2023 |  SFG | @ |  SDP | 0 | 16.88 | 4 | 0 | 0 | 0 | 2.2 | 5 | 5 | 5 | 1 | 0 | 0 | 0 | 14 | 0 | |
| 10 |  | A. Jackson | 4 | 4/14/2023 | LAD | vs | CHC | 0 | 22.50 | 1 | 0 | 0 | 0 | 2.0 | 6 | 5 | 5 | 1 | 0 | 1 | 0 | 13 | 0 | |
| 11 |  | E. Hernández | 4 | 6/3/2022 |  MIA | vs | SFG | 0 | 16.62 | 7 | 0 | 0 | 0 | 4.1 | 8 | 8 | 8 | 2 | 1 | 0 | 0 | 24 | 0 | |
| 12 |  | R. Weber | 4 | 6/13/2021 |  BOS | vs | TOR | 0 | 17.47 | 7 | 0 | 0 | 0 | 5.2 | 13 | 11 | 11 | 2 | 0 | 0 | 0 | 30 | 0 | |
| 13 | | J. Yamamoto | 4 | 9/9/2020 | MIA | @ |  ATL | 0 | 40.50 | 3 | 0 | 0 | 0 | 2.2 | 11 | 12 | 13 | 2 | 0 | 0 | 0 | 22 | 0 | |
| 14 |  | R. Ramirez | 4 | 8/16/2020 |  STL | @ |  CWS | 0 | 81.00 | 1 | 0 | 0 | 0 | 0.2 | 6 | 6 | 6 | 1 | 0 | 0 | 0 | 8 | 1 | |
| 15 | | A. Wilkerson | 4 | 8/18/2019 | MIL | @ |  WSH | 0 | 10.38 | 2 | 0 | 0 | 0 | 4.1 | 8 | 5 | 5 | 2 | 0 | 0 | 0 | 23 | 0 | |
| 16 |  | W. LeBlanc | 4 | 8/16/2019 |  SEA | @ | TOR | L | 0 | 9.00 | 3 | 0 | 0 | 0 | 7.0 | 11 | 7 | 7 | 1 | 0 | 1 | 0 | 31 | 0 |
| 17 |  | D. Gagnon | 4 | 8/15/2019 |  NYM | @ | ATL | 0 | 27.00 | 0 | 0 | 0 | 0 | 1.2 | 6 | 5 | 5 | 0 | 0 | 0 | 0 | 11 | 0 | |
| 18 |  | D. Straily | 4 | 6/14/2019 | BAL | vs | BOS | 0 | 47.25 | 2 | 0 | 0 | 0 | 1.1 | 7 | 7 | 7 | 0 | 1 | 0 | 0 | 12 | 0 | |
| 19 |  | C. Stammen | 4 | 6/9/2019 |  SDP | vs | WSH | L | 0 | 54.00 | 1 | 0 | 0 | 0 | 0.2 | 5 | 4 | 4 | 0 | 0 | 0 | 0 | 7 | 0 |
| 20 | | W. Chen | 4 | 4/9/2019 | MIA | @ | CIN | 0 | 45.00 | 3 | 0 | 0 | 0 | 2.0 | 7 | 10 | 10 | 2 | 1 | 0 | 0 | 16 | 0 | |
| 21 |  | M. Koch | 4 | 3/28/2019 |  ARI | @ | LAD | 0 | 10.38 | 0 | 0 | 0 | 0 | 4.1 | 5 | 5 | 5 | 1 | 0 | 1 | 0 | 19 | 0 | |
| 22 |  | L. Bard | 4 | 4/17/2018 |  LAA | vs | BOS | 0 | 32.40 | 1 | 0 | 0 | 0 | 1.2 | 6 | 6 | 6 | 0 | 1 | 0 | 0 | 12 | 0 | |
| 23 | | J. Grilli | 4 | 6/3/2017 | TOR | vs | NYY | 0 | 54.00 | 1 | 0 | 0 | 0 | 0.2 | 4 | 4 | 4 | 0 | 0 | 0 | 0 | 6 | 0 | |
| 24 | | A. Morgan | 4 | 4/11/2017 | PHI | vs | NYM | 0 | 9.82 | 5 | 0 | 0 | 0 | 3.2 | 7 | 4 | 4 | 2 | 0 | 0 | 1 | 20 | 0 | |
| 25 | | C. Villanueva | 4 | 8/16/2016 | SDP | @ |  TBR | 0 | 15.75 | 2 | 0 | 0 | 0 | 4.0 | 7 | 7 | 7 | 0 | 0 | 1 | 0 | 19 | 0 | |
Results may be incomplete. StatMuse has complete game-level data for home runs allowed going back to the 1901 season.
Some of the information used here was obtained free of charge from Retrosheet.
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