| SP | Clemens, R.Clemens, Roger >> | 42 | 2004 | R | 93 | 33 | 33 | 12 | 9 | 3.11 | .275 | 1.12 | 6.6 | 3.4 | 8.9 | 222.2 | 164 | 77 | 77 | 23 | 85 | 219 | 1 | 0 | 0 | 0 | 22 | 5 | 3 | 3.59 |
| SP | Peavy, J.Peavy, Jake # >> | 23 | 2004 | R | 86 | 33 | 33 | 11 | 12 | 4.37 | .297 | 1.24 | 8.2 | 3.0 | 10.1 | 203.2 | 185 | 105 | 99 | 37 | 68 | 227 | 0 | 0 | 0 | 0 | 20 | 5 | 2 | 4.21 |
| SP | Beckett, J.Beckett, Josh >> | 24 | 2004 | R | 83 | 32 | 32 | 13 | 15 | 4.10 | .296 | 1.25 | 7.3 | 4.0 | 6.9 | 199.2 | 162 | 98 | 91 | 21 | 88 | 153 | 1 | 0 | 0 | 0 | 17 | 2 | 5 | 4.19 |
| RP | Linebrink, S.Linebrink, Scott >> | 28 | 2004 | R | 83 | 89 | 0 | 3 | 5 | 4.26 | .301 | 1.25 | 8.0 | 3.2 | 6.6 | 114.0 | 101 | 54 | 54 | 13 | 41 | 83 | 0 | 6 | 8 | 0 | 0 | 5 | 3 | 4.24 |
| RP | Madson, R.Madson, Ryan >> | 24 | 2004 | R | 64 | 65 | 0 | 4 | 5 | 4.19 | .285 | 1.16 | 7.0 | 3.5 | 7.0 | 86.0 | 67 | 40 | 40 | 17 | 33 | 67 | 0 | 0 | 2 | 0 | 0 | 3 | 6 | 5.27 |
| RP | Mercker, K.Mercker, Kent >> | 36 | 2004 | L | 63 | 56 | 0 | 2 | 6 | 3.29 | .262 | 1.05 | 6.4 | 3.2 | 5.5 | 65.2 | 46 | 24 | 24 | 10 | 23 | 40 | 0 | 0 | 1 | 0 | 0 | 1 | 3 | 4.88 |
| CL | Benitez, A.Benitez, Armando † >> | 32 | 2004 | R | 95 | 74 | 0 | 4 | 4 | 2.88 | .240 | 0.92 | 5.2 | 3.2 | 7.4 | 68.2 | 39 | 24 | 22 | 9 | 24 | 56 | 0 | 39 | 5 | 0 | 0 | 2 | 0 | 4.22 |