The Cincinnati Reds have the most runs by a team in a game on May 9, with 21 runs against the Phillies on May 9, 1937.
| TEAM | R | DATE | TM | OPP | RESULT | AB | H | 2B | 3B | HR | RBI | BB | HBP | SO | SB | CS | PA | TB | XBH | SH | SF | IBB | GIDP | AVG | OBP | SLG | OPS | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | Reds | 21 | 5/9/1937 |  CIN | @ |  PHN | W 21-10 | 50 | 24 | 2 | 0 | 4 | 21 | 3 | 2 | 1 | 0 | 0 | 55 | 38 | 6 | 0 | 0 | .480 | .527 | .760 | 1.287 | ||
| 2 |  | Giants | 19 | 5/9/1899 |  NYG | vs |  WSH | W 19-1 | ||||||||||||||||||||||
| 3 |  | Bridegrooms | 19 | 5/9/1896 |  BKN | @ | CLE | W 19-8 | ||||||||||||||||||||||
| 4 | Colonels | 18 | 5/9/1888 | LOU | vs | KCC | W 18-6 | |||||||||||||||||||||||
| 5 |  | Giants | 18 | 5/9/1888 |  NYG | @ | IND | W 18-4 | ||||||||||||||||||||||
| 6 | | Red Stockings | 18 | 5/9/1887 | CIN | vs | CLE | W 18-2 | ||||||||||||||||||||||
| 7 |  | Alleghenys | 18 | 5/9/1883 |  PIT | vs | NYM | W 18-3 | ||||||||||||||||||||||
| 8 |  | Cardinals | 17 | 5/9/2019 |  STL | vs | PIT | W 17-4 | 41 | 16 | 6 | 0 | 0 | 15 | 8 | 1 | 10 | 0 | 0 | 50 | 22 | 6 | 0 | 0 | 0 | 1 | .390 | .500 | .537 | 1.037 |
| 9 |  | Brewers | 17 | 5/9/1996 |  MIL | vs |  BOS | W 17-2 | 40 | 17 | 3 | 1 | 1 | 17 | 10 | 0 | 10 | 4 | 0 | 53 | 25 | 5 | 0 | 3 | 0 | 0 | .425 | .509 | .625 | 1.134 |
| 10 | | Pirates | 17 | 5/9/1979 | PIT | @ |  ATL | W 17-9 | 43 | 14 | 2 | 0 | 3 | 15 | 3 | 3 | 3 | 1 | 0 | 50 | 25 | 5 | 1 | 0 | 0 | 0 | .326 | .408 | .581 | .990 |
| 11 | | Giants | 17 | 5/9/1951 | NYG | vs | SLN | W 17-3 | 44 | 21 | 1 | 1 | 3 | 17 | 5 | 0 | 4 | 2 | 0 | 49 | 33 | 5 | 0 | 0 | 1 | .477 | .531 | .750 | 1.281 | |
| 12 | | Giants | 17 | 5/9/1940 | NYG | @ |  PIT | W 17-6 | 45 | 15 | 2 | 0 | 0 | 15 | 10 | 3 | 3 | 1 | 0 | 58 | 17 | 2 | 0 | 2 | .333 | .483 | .378 | .861 | ||
| 13 |  | Tigers | 17 | 5/9/1927 |  DET | vs |  BSA | W 17-11 | 41 | 22 | 2 | 3 | 3 | 17 | 6 | 0 | 2 | 1 | 1 | 49 | 39 | 8 | 2 | .537 | .596 | .951 | 1.547 | |||
| 14 |  | Beaneaters | 17 | 5/9/1896 |  BSN | @ | LOU | W 17-5 | ||||||||||||||||||||||
| 15 | Wolverines | 17 | 5/9/1883 | DET | @ |  CWS | W 17-7 | |||||||||||||||||||||||
| 16 | | Cardinals | 16 | 5/9/1996 | STL | vs | SFG | W 16-8 | 37 | 16 | 3 | 0 | 2 | 16 | 8 | 0 | 3 | 0 | 1 | 46 | 25 | 5 | 1 | 0 | 1 | 2 | .432 | .533 | .676 | 1.209 |
| 17 |  | Brewers | 16 | 5/9/1986 |  MIL | @ |  CAL | W 16-5 | 43 | 18 | 4 | 0 | 2 | 15 | 7 | 1 | 5 | 1 | 0 | 53 | 28 | 6 | 1 | 1 | 0 | 1 | .419 | .500 | .651 | 1.151 |
| 18 | | Tigers | 16 | 5/9/1916 | DET | @ |  PHA | W 16-2 | 36 | 12 | 4 | 0 | 0 | 14 | 18 | 0 | 3 | 1 | 56 | 16 | 4 | 2 | .333 | .556 | .444 | 1.000 | ||||
| 19 |  | Orioles | 16 | 5/9/1891 |  BAL | vs | LOU | W 16-6 | ||||||||||||||||||||||
| 20 | | Giants | 16 | 5/9/1890 | NYN | vs | BSN | W 16-3 | ||||||||||||||||||||||
| 21 | | Alleghenys | 16 | 5/9/1885 | PIT | vs | NYM | W 16-3 | ||||||||||||||||||||||
| 22 |  | Twins | 15 | 5/9/2006 |  MIN | @ |  TEX | W 15-5 | 46 | 19 | 5 | 1 | 2 | 15 | 6 | 0 | 4 | 0 | 0 | 52 | 32 | 8 | 0 | 0 | 0 | 1 | .413 | .481 | .696 | 1.176 |
| 23 |  | Orioles | 15 | 5/9/2003 |  BAL | @ |  KCR | W 15-5 | 42 | 17 | 3 | 1 | 2 | 15 | 4 | 0 | 4 | 0 | 0 | 48 | 28 | 6 | 2 | 0 | 0 | 1 | .405 | .457 | .667 | 1.123 |
| 24 |  | Athletics | 15 | 5/9/1998 |  OAK | vs |  CWS | W 15-7 | 37 | 17 | 5 | 0 | 1 | 14 | 6 | 0 | 3 | 2 | 1 | 44 | 25 | 6 | 1 | 0 | 1 | 1 | .459 | .535 | .676 | 1.211 |
| 25 |  | Orioles | 15 | 5/9/1987 |  BAL | @ |  CWS | W 15-6 | 44 | 17 | 3 | 1 | 6 | 15 | 5 | 0 | 5 | 0 | 0 | 49 | 40 | 10 | 0 | 0 | 0 | 0 | .386 | .449 | .909 | 1.358 |
Results may be incomplete. StatMuse has complete team, game-level data for runs going back to the 1901 season.
Some of the information used here was obtained free of charge from Retrosheet.
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