Brickyard Kennedy has allowed the most runs in a postseason game, with 10 runs in Game 5 of the 1903 World Series against the Boston Americans.
Interpreted as:
most runs allowed by a player in a playoff game| NAME | R | DATE | TM | OPP | DEC | GS | ERA | SO | CG | SHO | SV | IP | H | ER | HR | BB | HBP | GF | IBB | TBF | WP | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | B. Kennedy | 10 | 10/7/1903 |  PIT | vs |  BSA | L | 1 | 5.14 | 3 | 0 | 0 | 0 | 7.0 | 10 | 4 | 0 | 3 | 0 | 0 | 0 | 38 | 0 |
| 2 |  | J. Witasick | 9 | 11/3/2001 |  NYY | @ |  ARI | 0 | 54.00 | 4 | 0 | 0 | 0 | 1.1 | 10 | 8 | 0 | 0 | 0 | 0 | 0 | 14 | 1 | |
| 3 |  | P. Niekro | 9 | 10/4/1969 |  ATL | vs |  NYM | L | 1 | 4.50 | 4 | 0 | 0 | 0 | 8.0 | 9 | 4 | 0 | 4 | 0 | 0 | 1 | 36 | 0 |
| 4 |  | W. Johnson | 9 | 10/15/1925 |  WSH | @ | PIT | L | 1 | 5.63 | 3 | 1 | 0 | 0 | 8.0 | 15 | 5 | 0 | 1 | 0 | 0 | 0 | 40 | 0 |
| 5 |  | M. Brown | 9 | 10/18/1910 |  CHC | @ |  PHA | L | 1 | 9.00 | 6 | 0 | 0 | 0 | 7.0 | 13 | 7 | 0 | 4 | 0 | 0 | 0 | 38 | 0 |
| 6 |  | A. Coakley | 9 | 10/12/1905 | PHA | vs |  NYG | L | 1 | 3.00 | 2 | 1 | 0 | 0 | 9.0 | 9 | 3 | 0 | 5 | 1 | 0 | 1 | 40 | 0 |
| 7 |  | J. Flaherty | 8 | 10/18/2024 |  LAD | @ | NYM | L | 1 | 24.00 | 0 | 0 | 0 | 0 | 3.0 | 8 | 8 | 1 | 4 | 0 | 0 | 0 | 21 | 0 |
| 8 | | G. Dayton | 8 | 10/14/2020 | ATL | vs | LAD | 0 | 36.00 | 2 | 0 | 0 | 0 | 2.0 | 8 | 8 | 3 | 1 | 1 | 0 | 0 | 16 | 0 | |
| 9 |  | J. Cueto | 8 | 10/19/2015 |  KCR | @ |  TOR | L | 1 | 36.00 | 2 | 0 | 0 | 0 | 2.0 | 6 | 8 | 1 | 4 | 1 | 0 | 0 | 17 | 0 |
| 10 |  | C. Kershaw | 8 | 10/3/2014 | LAD | vs |  STL | L | 1 | 10.80 | 10 | 0 | 0 | 0 | 6.2 | 8 | 8 | 2 | 0 | 0 | 0 | 0 | 28 | 0 |
| 11 |  | M. Moore | 8 | 10/4/2013 |  TBR | @ |  BOS | L | 1 | 14.54 | 4 | 0 | 0 | 0 | 4.1 | 8 | 7 | 0 | 2 | 1 | 0 | 1 | 25 | 1 |
| 12 |  | C.J. Wilson | 8 | 9/30/2011 |  TEX | vs | TBR | L | 1 | 10.80 | 6 | 0 | 0 | 0 | 5.0 | 7 | 6 | 3 | 1 | 1 | 0 | 0 | 25 | 0 |
| 13 |  | J. Beckett | 8 | 10/11/2008 | BOS | @ | TBR | 1 | 16.62 | 5 | 0 | 0 | 0 | 4.1 | 9 | 8 | 3 | 1 | 0 | 0 | 0 | 22 | 0 | |
| 14 |  | C. Billingsley | 8 | 10/10/2008 | LAD | @ |  PHI | L | 1 | 27.00 | 5 | 0 | 0 | 0 | 2.1 | 8 | 7 | 0 | 3 | 0 | 0 | 1 | 18 | 0 |
| 15 |  | CC Sabathia | 8 | 10/12/2007 |  CLE | @ | BOS | L | 1 | 16.62 | 3 | 0 | 0 | 0 | 4.1 | 7 | 8 | 0 | 5 | 1 | 0 | 1 | 24 | 0 |
| 16 | | C. Wang | 8 | 10/4/2007 | NYY | @ | CLE | L | 1 | 15.43 | 2 | 0 | 0 | 0 | 4.2 | 9 | 8 | 2 | 4 | 1 | 0 | 0 | 25 | 0 |
| 17 | | M. Clement | 8 | 10/4/2005 | BOS | @ |  CWS | L | 1 | 21.60 | 0 | 0 | 0 | 0 | 3.1 | 7 | 8 | 3 | 0 | 2 | 0 | 0 | 18 | 0 |
| 18 |  | J. Peavy | 8 | 10/4/2005 |  SDP | @ | STL | L | 1 | 16.62 | 3 | 0 | 0 | 0 | 4.1 | 8 | 8 | 2 | 3 | 0 | 0 | 2 | 23 | 1 |
| 19 | | D. Wells | 8 | 10/5/2002 | NYY | @ |  ANA | L | 1 | 15.43 | 0 | 0 | 0 | 0 | 4.2 | 10 | 8 | 1 | 0 | 0 | 0 | 0 | 24 | 0 |
| 20 |  | P. Abbott | 8 | 10/13/2001 |  SEA | @ | CLE | 0 | 24.00 | 3 | 0 | 0 | 0 | 3.0 | 9 | 8 | 3 | 5 | 0 | 0 | 0 | 22 | 0 | |
| 21 | | H. Irabu | 8 | 10/16/1999 | NYY | @ | BOS | 0 | 13.50 | 3 | 0 | 0 | 0 | 4.2 | 13 | 7 | 2 | 0 | 0 | 0 | 0 | 27 | 0 | |
| 22 |  | C. Nagy | 8 | 10/11/1999 | CLE | vs | BOS | 1 | 21.00 | 2 | 0 | 0 | 0 | 3.0 | 6 | 7 | 2 | 2 | 0 | 0 | 1 | 17 | 0 | |
| 23 | | S. Reed | 8 | 10/10/1999 | CLE | @ | BOS | 0 | 54.00 | 1 | 0 | 0 | 0 | 1.1 | 7 | 8 | 1 | 1 | 2 | 0 | 0 | 14 | 0 | |
| 24 |  | G. Maddux | 8 | 10/10/1996 | ATL | vs | STL | L | 1 | 4.05 | 3 | 0 | 0 | 0 | 6.2 | 9 | 3 | 1 | 2 | 0 | 0 | 1 | 32 | 1 |
| 25 | | T. Glavine | 8 | 10/13/1992 | ATL | vs |  PIT | L | 1 | 63.00 | 0 | 0 | 0 | 0 | 1.0 | 6 | 7 | 2 | 0 | 1 | 0 | 0 | 11 | 0 |
Results may be incomplete. StatMuse has complete game-level data for runs allowed going back to the 1903 playoffs.
Some of the information used here was obtained free of charge from Retrosheet.
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