Before 2013, 22 teams were tied for the best record in a month, with a record of 3-0. The first three are the Oakland Athletics in October 2012 and in October 2010, the New York Yankees in October 2012 and in March 2011 and the Toronto Blue Jays in October 2012.
| TEAM | REC | MONTH | W% | G | W | L | AB | R | H | 2B | 3B | HR | RBI | BB | HBP | SO | SB | CS | PA | TB | XBH | SH | SF | IBB | GIDP | AVG | OBP | SLG | OPS | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | Athletics | 3-0 | October 2012 | 1.000 | 3 | 3 | 0 | 97 | 19 | 26 | 6 | 0 | 2 | 14 | 10 | 0 | 22 | 1 | 1 | 108 | 38 | 8 | 0 | 1 | 0 | 2 | .268 | .333 | .392 | .725 |
| 2 |  | Yankees | 3-0 | October 2012 | 1.000 | 3 | 3 | 0 | 121 | 28 | 44 | 9 | 0 | 9 | 28 | 16 | 1 | 19 | 2 | 1 | 140 | 80 | 18 | 0 | 2 | 1 | 3 | .364 | .436 | .661 | 1.097 |
| 3 |  | Blue Jays | 3-0 | October 2012 | 1.000 | 3 | 3 | 0 | 94 | 12 | 24 | 3 | 1 | 2 | 12 | 10 | 0 | 19 | 2 | 0 | 106 | 35 | 6 | 2 | 0 | 0 | 5 | .255 | .327 | .372 | .699 |
| 4 |  | Braves | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 31 | 2 | 5 | 1 | 0 | 1 | 2 | 1 | 0 | 5 | 0 | 0 | 32 | 9 | 2 | 0 | 0 | 0 | 1 | .161 | .188 | .290 | .478 |
| 5 |  | Reds | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 35 | 7 | 12 | 1 | 0 | 3 | 7 | 4 | 0 | 10 | 0 | 0 | 43 | 22 | 4 | 2 | 2 | 0 | 0 | .343 | .390 | .629 | 1.019 |
| 6 |  | Dodgers | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 30 | 2 | 6 | 1 | 0 | 0 | 1 | 4 | 1 | 6 | 1 | 0 | 35 | 7 | 1 | 0 | 0 | 1 | 0 | .200 | .314 | .233 | .548 |
| 7 | | Yankees | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 26 | 6 | 5 | 1 | 0 | 2 | 6 | 5 | 0 | 8 | 1 | 0 | 34 | 12 | 3 | 2 | 1 | 0 | 0 | .192 | .313 | .462 | .774 |
| 8 |  | Angels | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 38 | 4 | 12 | 4 | 0 | 2 | 4 | 1 | 1 | 9 | 1 | 0 | 41 | 22 | 6 | 1 | 0 | 0 | 0 | .316 | .350 | .579 | .929 |
| 9 |  | Padres | 1-0 | March 2011 | 1.000 | 1 | 1 | 0 | 39 | 5 | 8 | 2 | 0 | 1 | 4 | 3 | 2 | 6 | 1 | 0 | 45 | 13 | 3 | 0 | 1 | 0 | 1 | .205 | .289 | .333 | .622 |
| 10 |  | Cardinals | 3-0 | October 2010 | 1.000 | 3 | 3 | 0 | 98 | 10 | 21 | 3 | 0 | 0 | 7 | 11 | 1 | 17 | 1 | 2 | 111 | 24 | 3 | 1 | 0 | 1 | 1 | .214 | .300 | .245 | .545 |
| 11 | | Athletics | 3-0 | October 2010 | 1.000 | 3 | 3 | 0 | 104 | 18 | 26 | 4 | 0 | 7 | 18 | 9 | 0 | 16 | 3 | 1 | 114 | 51 | 11 | 0 | 1 | 0 | 1 | .250 | .307 | .490 | .797 |
| 12 |  | Mets | 3-0 | October 2009 | 1.000 | 3 | 3 | 0 | 99 | 16 | 33 | 9 | 3 | 2 | 14 | 12 | 0 | 12 | 4 | 1 | 115 | 54 | 14 | 1 | 3 | 1 | 1 | .333 | .395 | .545 | .940 |
| 13 |  | Red Sox | 4-0 | October 2009 | 1.000 | 4 | 4 | 0 | 132 | 32 | 42 | 6 | 0 | 9 | 30 | 20 | 2 | 21 | 3 | 2 | 157 | 75 | 15 | 0 | 3 | 1 | 1 | .318 | .408 | .568 | .976 |
| 14 |  | Orioles | 4-0 | October 2009 | 1.000 | 4 | 4 | 0 | 144 | 27 | 40 | 7 | 0 | 4 | 26 | 14 | 2 | 29 | 4 | 1 | 162 | 59 | 11 | 2 | 0 | 0 | 1 | .278 | .350 | .410 | .760 |
| 15 |  | Twins | 5-0 | October 2009 | 1.000 | 5 | 5 | 0 | 181 | 42 | 56 | 10 | 2 | 10 | 41 | 23 | 4 | 31 | 2 | 1 | 213 | 100 | 22 | 3 | 2 | 3 | 0 | .309 | .395 | .552 | .948 |
| 16 |  | Nationals | 4-0 | October 2009 | 1.000 | 4 | 4 | 0 | 162 | 16 | 39 | 12 | 2 | 3 | 15 | 20 | 0 | 46 | 2 | 2 | 184 | 64 | 17 | 2 | 0 | 2 | 5 | .241 | .324 | .395 | .719 |
| 17 |  | Pirates | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 49 | 12 | 17 | 5 | 0 | 3 | 10 | 7 | 0 | 11 | 0 | 0 | 60 | 31 | 8 | 4 | 0 | 1 | 1 | .347 | .429 | .633 | 1.061 |
| 18 | | Dodgers | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 31 | 5 | 11 | 1 | 0 | 1 | 5 | 4 | 0 | 3 | 1 | 0 | 37 | 15 | 2 | 2 | 0 | 0 | 2 | .355 | .429 | .484 | .912 |
| 19 |  | Indians | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 35 | 10 | 12 | 2 | 0 | 2 | 10 | 3 | 0 | 9 | 0 | 0 | 38 | 20 | 4 | 0 | 0 | 1 | 0 | .343 | .395 | .571 | .966 |
| 20 | | Twins | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 33 | 3 | 10 | 3 | 0 | 0 | 3 | 3 | 0 | 6 | 4 | 0 | 36 | 13 | 3 | 0 | 0 | 1 | 0 | .303 | .361 | .394 | .755 |
| 21 | | Mets | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 34 | 7 | 10 | 5 | 0 | 0 | 6 | 5 | 0 | 3 | 1 | 2 | 40 | 15 | 5 | 1 | 0 | 0 | 0 | .294 | .385 | .441 | .826 |
| 22 |  | Royals | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 42 | 5 | 10 | 0 | 1 | 1 | 5 | 3 | 1 | 10 | 2 | 0 | 47 | 15 | 2 | 1 | 0 | 0 | 0 | .238 | .304 | .357 | .661 |
| 23 | | Padres | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 36 | 4 | 14 | 3 | 0 | 0 | 4 | 3 | 0 | 8 | 0 | 0 | 40 | 17 | 3 | 0 | 1 | 0 | 1 | .389 | .425 | .472 | .897 |
| 24 |  | Brewers | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 33 | 4 | 7 | 3 | 0 | 0 | 4 | 2 | 2 | 9 | 1 | 0 | 40 | 10 | 3 | 2 | 1 | 1 | 0 | .212 | .289 | .303 | .593 |
| 25 |  | Mariners | 1-0 | March 2008 | 1.000 | 1 | 1 | 0 | 28 | 5 | 6 | 1 | 0 | 0 | 4 | 7 | 0 | 5 | 0 | 2 | 35 | 7 | 1 | 0 | 0 | 1 | 1 | .214 | .371 | .250 | .621 |
Some of the information used here was obtained free of charge from Retrosheet.
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