| 2012 NL Leaders | |||||||||||||||||
| Name | Age | Team | G | W | L | IP | TBF | H | 2B | 3B | HR | R | ER | BB | SO | ERA | RA9 |
| Joseph Paterson | Arizona | 6 | 0 | 0 | 2.2 | 26 | 15 | 4 | 0 | 2 | 11 | 11 | 3 | 0 | 37.08 | 37.08 | |
| John Ely | LA Dodgers | 2 | 0 | 2 | 2.2 | 19 | 6 | 1 | 0 | 0 | 6 | 6 | 4 | 3 | 20.22 | 20.22 | |
| Francisco Cordero | 37 | Houston | 6 | 3 | 8 | 5.0 | 32 | 13 | 4 | 0 | 2 | 11 | 11 | 4 | 5 | 19.80 | 19.80 |
| Edwar Cabrera | 25 | Colorado | 2 | 0 | 2 | 5.2 | 33 | 9 | 1 | 0 | 3 | 9 | 7 | 7 | 5 | 11.11 | 14.29 |
| Christopher Schwinden | 26 | NY Mets | 3 | 0 | 1 | 8.2 | 46 | 15 | 2 | 2 | 4 | 13 | 12 | 3 | 1 | 12.46 | 13.49 |
| Rick Vanden Hurk | Pittsburgh | 4 | 0 | 1 | 2.2 | 16 | 5 | 0 | 0 | 0 | 4 | 4 | 1 | 3 | 13.48 | 13.48 | |
| Jorge De La Rosa | 31 | Colorado | 3 | 0 | 2 | 10.2 | 53 | 17 | 3 | 0 | 5 | 14 | 11 | 2 | 6 | 9.28 | 11.81 |
| Todd Redmond | 27 | Cincinnati | 1 | 0 | 1 | 3.1 | 22 | 7 | 1 | 0 | 1 | 4 | 4 | 5 | 2 | 10.81 | 10.81 |
| Travis Blackley | 30 | San Francisco | 4 | 0 | 0 | 5.0 | 25 | 7 | 0 | 2 | 0 | 6 | 5 | 2 | 2 | 9.00 | 10.80 |
| Takashi Saito | 42 | Arizona | 16 | 0 | 0 | 12.0 | 60 | 17 | 8 | 0 | 4 | 14 | 9 | 5 | 11 | 6.75 | 10.50 |
| Blake Parker | 27 | Chi Cubs | 7 | 0 | 0 | 6.0 | 32 | 10 | 0 | 0 | 3 | 7 | 4 | 5 | 6 | 6.00 | 10.50 |
| Pedro Beato | 26 | NY Mets | 7 | 0 | 0 | 4.1 | 20 | 5 | 1 | 0 | 1 | 5 | 5 | 2 | 5 | 10.39 | 10.39 |
| Jonathan Sanchez | 30 | Colorado | 3 | 1 | 9 | 11.1 | 57 | 17 | 3 | 3 | 3 | 13 | 12 | 9 | 9 | 9.53 | 10.33 |
| J.C. Romero | 36 | St. Louis | 11 | 0 | 0 | 8.0 | 41 | 14 | 2 | 0 | 3 | 9 | 9 | 2 | 5 | 10.13 | 10.13 |
| Ryan Perry | Washington | 7 | 1 | 0 | 8.0 | 35 | 12 | 2 | 1 | 2 | 9 | 9 | 2 | 3 | 10.13 | 10.13 | |
| Vinnie Chulk | 34 | Milwaukee | 7 | 1 | 0 | 9.0 | 48 | 17 | 5 | 1 | 0 | 10 | 10 | 4 | 10 | 10.00 | 10.00 |
| Brian Sanches | 34 | Philadelphia | 6 | 0 | 1 | 6.1 | 34 | 12 | 2 | 0 | 4 | 7 | 7 | 3 | 5 | 9.95 | 9.95 |
| Enerio Del Rosario | 27 | Houston | 19 | 0 | 0 | 19.0 | 97 | 34 | 9 | 1 | 1 | 21 | 19 | 7 | 11 | 9.00 | 9.95 |
| Brandon Dickson | 28 | St. Louis | 4 | 0 | 0 | 6.1 | 32 | 10 | 1 | 1 | 2 | 7 | 5 | 2 | 6 | 7.11 | 9.95 |
| Brad Lidge | 36 | Washington | 11 | 0 | 1 | 9.1 | 51 | 12 | 5 | 1 | 1 | 10 | 10 | 11 | 10 | 9.65 | 9.65 |
| Michael Stutes | 26 | Philadelphia | 6 | 0 | 0 | 5.2 | 29 | 7 | 2 | 1 | 0 | 6 | 4 | 4 | 5 | 6.35 | 9.52 |
| William Harris | 28 | Colorado | 20 | 1 | 1 | 17.2 | 89 | 27 | 6 | 0 | 3 | 18 | 16 | 6 | 19 | 8.15 | 9.17 |
| Brian Wilson | 30 | San Francisco | 2 | 0 | 0 | 2.0 | 12 | 4 | 2 | 0 | 0 | 2 | 2 | 2 | 2 | 9.00 | 9.00 |
| Lendy Castillo | 23 | Chi Cubs | 13 | 0 | 1 | 16.0 | 88 | 24 | 3 | 0 | 2 | 16 | 14 | 12 | 13 | 7.88 | 9.00 |
| Jonathan Albaladejo | 30 | Arizona | 3 | 0 | 0 | 3.0 | 15 | 5 | 2 | 0 | 1 | 3 | 3 | 0 | 2 | 9.00 | 9.00 |
| Matt Palmer | 33 | San Diego | 3 | 0 | 0 | 2.0 | 10 | 2 | 0 | 0 | 1 | 2 | 2 | 2 | 2 | 9.00 | 9.00 |
| Brian Fuentes | 37 | St. Louis | 6 | 2 | 2 | 5.0 | 26 | 6 | 1 | 0 | 1 | 5 | 5 | 5 | 6 | 9.00 | 9.00 |
| Dustin Moseley | 31 | San Diego | 1 | 0 | 0 | 5.0 | 22 | 5 | 2 | 0 | 1 | 5 | 5 | 2 | 4 | 9.00 | 9.00 |
| Collin McHugh | NY Mets | 8 | 0 | 4 | 21.1 | 99 | 27 | 5 | 5 | 5 | 21 | 18 | 8 | 17 | 7.59 | 8.86 | |
| Hisanori Takahashi | Pittsburgh | 9 | 0 | 3 | 8.1 | 39 | 10 | 2 | 0 | 2 | 8 | 8 | 4 | 11 | 8.64 | 8.64 | |
