Josh Hader has the highest career K/9 by a relief pitcher when pitching at least 200 innings, with 14.56 per nine innings.
| NAME | K/9 | IP | G | W | L | W% | GS | ERA | SO | CG | SHO | SV | H | ER | R | HR | BB | HBP | GF | IBB | TBF | WP | BB/9 | K/BB | HR/9 | K% | BB% | WHIP | BABIP | RA | H/9 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | J. Hader | 14.56 | 512.1 | 468 | 34 | 31 | .523 | 0 | 2.64 | 829 | 0 | 0 | 226 | 282 | 150 | 164 | 65 | 198 | 24 | 321 | 6 | 2,019 | 19 | 3.48 | 4.19 | 1.14 | 41.1 | 9.8 | 0.94 | .240 | 2.88 | 4.95 |
| 2 |  | E. DÃaz | 14.55 | 525.1 | 527 | 29 | 36 | .446 | 0 | 2.91 | 849 | 0 | 0 | 257 | 365 | 170 | 183 | 55 | 187 | 41 | 401 | 10 | 2,138 | 34 | 3.20 | 4.54 | 0.94 | 39.7 | 8.7 | 1.05 | .308 | 3.14 | 6.25 |
| 3 |  | A. Chapman | 14.54 | 837.0 | 879 | 60 | 48 | .556 | 0 | 2.48 | 1,352 | 0 | 0 | 377 | 482 | 231 | 256 | 54 | 415 | 34 | 575 | 7 | 3,402 | 88 | 4.46 | 3.26 | 0.58 | 39.7 | 12.2 | 1.07 | .277 | 2.75 | 5.18 |
| 4 |  | D. Betances | 14.47 | 392.1 | 373 | 21 | 23 | .477 | 0 | 2.55 | 631 | 0 | 0 | 36 | 239 | 111 | 124 | 26 | 181 | 28 | 86 | 5 | 1,604 | 28 | 4.15 | 3.49 | 0.60 | 39.3 | 11.3 | 1.07 | .289 | 2.84 | 5.48 |
| 5 | | D. Williams | 14.05 | 313.1 | 326 | 34 | 17 | .667 | 0 | 2.56 | 489 | 0 | 0 | 92 | 189 | 89 | 108 | 21 | 145 | 15 | 136 | 4 | 1,279 | 17 | 4.16 | 3.37 | 0.60 | 38.2 | 11.3 | 1.07 | .276 | 3.10 | 5.43 |
| 6 |  | C. Kimbrel | 13.99 | 833.0 | 863 | 56 | 50 | .528 | 0 | 2.64 | 1,295 | 0 | 0 | 440 | 504 | 244 | 272 | 77 | 352 | 40 | 663 | 12 | 3,355 | 71 | 3.80 | 3.68 | 0.83 | 38.6 | 10.5 | 1.03 | .268 | 2.94 | 5.45 |
| 7 | | F. Cruz | 13.37 | 202.0 | 205 | 10 | 15 | .400 | 0 | 4.19 | 300 | 0 | 0 | 2 | 156 | 94 | 100 | 21 | 106 | 8 | 27 | 2 | 867 | 21 | 4.72 | 2.83 | 0.94 | 34.6 | 12.2 | 1.30 | .313 | 4.46 | 6.95 |
| 8 | | A. Miller | 12.93 | 504.0 | 546 | 35 | 28 | .556 | 0 | 2.95 | 724 | 0 | 0 | 63 | 351 | 165 | 183 | 47 | 201 | 46 | 147 | 9 | 2,091 | 25 | 3.59 | 3.60 | 0.84 | 34.6 | 9.6 | 1.10 | .283 | 3.27 | 6.27 |
| 9 |  | A. Muñoz | 12.47 | 276.1 | 281 | 15 | 26 | .366 | 0 | 2.61 | 383 | 0 | 0 | 86 | 182 | 80 | 95 | 20 | 111 | 16 | 137 | 12 | 1,120 | 20 | 3.62 | 3.45 | 0.65 | 34.2 | 9.9 | 1.06 | .275 | 3.09 | 5.93 |
| 10 |  | K. Jansen | 12.41 | 939.2 | 949 | 55 | 42 | .567 | 0 | 2.59 | 1,296 | 0 | 0 | 482 | 618 | 270 | 289 | 91 | 287 | 32 | 713 | 20 | 3,729 | 21 | 2.75 | 4.52 | 0.87 | 34.8 | 7.7 | 0.96 | .261 | 2.77 | 5.92 |
| 11 | | K. Yates | 12.41 | 456.1 | 476 | 30 | 24 | .556 | 0 | 3.37 | 629 | 0 | 0 | 98 | 335 | 171 | 185 | 63 | 182 | 29 | 211 | 13 | 1,898 | 18 | 3.59 | 3.46 | 1.24 | 33.1 | 9.6 | 1.13 | .273 | 3.65 | 6.61 |
| 12 | | C. Marmol | 12.33 | 509.1 | 506 | 18 | 29 | .383 | 0 | 3.25 | 698 | 0 | 0 | 117 | 324 | 184 | 195 | 37 | 340 | 47 | 259 | 20 | 2,207 | 32 | 6.01 | 2.05 | 0.65 | 31.6 | 15.4 | 1.30 | .265 | 3.45 | 5.73 |
| 13 | | K. Giles | 12.26 | 355.1 | 362 | 14 | 18 | .438 | 0 | 2.71 | 484 | 0 | 0 | 115 | 283 | 107 | 121 | 28 | 114 | 5 | 208 | 5 | 1,454 | 24 | 2.89 | 4.25 | 0.71 | 33.3 | 7.8 | 1.12 | .310 | 3.06 | 7.17 |
| 14 | | B. Abreu | 12.25 | 344.2 | 333 | 18 | 14 | .563 | 0 | 2.87 | 469 | 0 | 0 | 18 | 253 | 110 | 121 | 29 | 166 | 23 | 73 | 0 | 1,445 | 23 | 4.33 | 2.83 | 0.76 | 32.5 | 11.5 | 1.22 | .296 | 3.16 | 6.61 |
| 15 | | R. Dibble | 12.17 | 477.0 | 385 | 27 | 25 | .519 | 0 | 2.98 | 645 | 0 | 0 | 89 | 332 | 158 | 169 | 27 | 238 | 12 | 204 | 25 | 1,979 | 36 | 4.49 | 2.71 | 0.51 | 32.6 | 12.0 | 1.19 | .289 | 3.19 | 6.26 |
| 16 | | A. Vesia | 12.12 | 289.2 | 319 | 18 | 14 | .563 | 0 | 2.92 | 390 | 0 | 0 | 15 | 190 | 94 | 113 | 34 | 133 | 12 | 47 | 13 | 1,193 | 9 | 4.13 | 2.93 | 1.06 | 32.7 | 11.1 | 1.12 | .250 | 3.51 | 5.90 |
| 17 | | T. Rosenthal | 12.12 | 364.0 | 373 | 12 | 25 | .324 | 0 | 3.36 | 490 | 0 | 0 | 132 | 304 | 136 | 145 | 19 | 177 | 22 | 207 | 8 | 1,570 | 23 | 4.38 | 2.77 | 0.47 | 31.2 | 11.3 | 1.32 | .331 | 3.59 | 7.52 |
| 18 | | C. Knebel | 12.05 | 301.0 | 308 | 13 | 16 | .448 | 0 | 3.29 | 403 | 0 | 0 | 72 | 231 | 110 | 121 | 34 | 143 | 11 | 137 | 13 | 1,260 | 7 | 4.28 | 2.82 | 1.02 | 32.0 | 11.3 | 1.24 | .294 | 3.62 | 6.91 |
| 19 | | B. Wagner | 11.92 | 903.0 | 853 | 47 | 40 | .540 | 0 | 2.31 | 1,196 | 0 | 0 | 422 | 601 | 232 | 262 | 82 | 300 | 33 | 703 | 26 | 3,600 | 43 | 2.99 | 3.99 | 0.82 | 33.2 | 8.3 | 1.00 | .261 | 2.61 | 5.99 |
| 20 | | B. Lidge | 11.92 | 600.1 | 602 | 26 | 32 | .448 | 0 | 3.55 | 795 | 0 | 0 | 225 | 490 | 237 | 257 | 57 | 285 | 33 | 368 | 41 | 2,576 | 46 | 4.27 | 2.79 | 0.85 | 30.9 | 11.1 | 1.29 | .308 | 3.85 | 7.35 |
| 21 | | D. Robertson | 11.84 | 893.1 | 880 | 68 | 46 | .596 | 0 | 2.93 | 1,175 | 0 | 0 | 179 | 674 | 291 | 315 | 81 | 364 | 25 | 358 | 38 | 3,687 | 57 | 3.67 | 3.23 | 0.82 | 31.9 | 9.9 | 1.16 | .290 | 3.17 | 6.79 |
| 22 | | M. Feliz | 11.82 | 249.2 | 227 | 17 | 8 | .680 | 0 | 5.12 | 328 | 0 | 0 | 1 | 237 | 142 | 151 | 42 | 108 | 7 | 54 | 2 | 1,091 | 18 | 3.89 | 3.04 | 1.51 | 30.1 | 9.9 | 1.38 | .322 | 5.44 | 8.54 |
| 23 | | J. Leclerc | 11.74 | 365.2 | 357 | 12 | 21 | .364 | 0 | 3.35 | 477 | 0 | 0 | 41 | 247 | 136 | 150 | 32 | 203 | 21 | 141 | 8 | 1,546 | 25 | 5.00 | 2.35 | 0.79 | 30.9 | 13.1 | 1.23 | .264 | 3.69 | 6.08 |
| 24 | | L. Hendriks | 11.73 | 482.0 | 446 | 30 | 21 | .588 | 0 | 3.16 | 628 | 0 | 0 | 116 | 408 | 169 | 190 | 49 | 111 | 9 | 218 | 13 | 1,953 | 36 | 2.07 | 5.66 | 0.91 | 32.2 | 5.7 | 1.08 | .311 | 3.55 | 7.62 |
| 25 | | E. Gagne | 11.70 | 378.1 | 354 | 23 | 13 | .639 | 0 | 2.62 | 492 | 0 | 0 | 187 | 264 | 110 | 115 | 33 | 113 | 15 | 269 | 12 | 1,505 | 10 | 2.69 | 4.35 | 0.79 | 32.7 | 7.5 | 1.00 | .271 | 2.74 | 6.28 |
StatMuse has game-level data for K/9 and innings pitched going back to the 1901 season.
Some of the information used here was obtained free of charge from Retrosheet.
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| NL East | W | L | PCT | GB |
|---|---|---|---|---|
32 | 15 | .681 | ||
24 | 23 | .511 | 8.0 | |
23 | 24 | .489 | 9.0 | |
21 | 26 | .447 | 11.0 | |
20 | 26 | .435 | 11.5 | |
| NL Central | W | L | PCT | GB |
29 | 18 | .617 | ||
26 | 18 | .591 | 1.5 | |
27 | 19 | .587 | 1.5 | |
24 | 23 | .511 | 5.0 | |
24 | 23 | .511 | 5.0 | |
| NL West | W | L | PCT | GB |
29 | 18 | .617 | ||
27 | 18 | .600 | 1.0 | |
22 | 23 | .489 | 6.0 | |
20 | 27 | .426 | 9.0 | |
18 | 29 | .383 | 11.0 |
Braves
Phillies
Nationals
Marlins
Mets
Padres
Diamondbacks
Giants
Rockies| AL East | W | L | PCT | GB |
|---|---|---|---|---|
30 | 15 | .667 | ||
28 | 19 | .596 | 3.0 | |
21 | 25 | .457 | 9.5 | |
21 | 26 | .447 | 10.0 | |
19 | 27 | .413 | 11.5 | |
| AL Central | W | L | PCT | GB |
26 | 22 | .542 | ||
24 | 22 | .522 | 1.0 | |
21 | 26 | .447 | 4.5 | |
20 | 27 | .426 | 5.5 | |
20 | 27 | .426 | 5.5 | |
| AL West | W | L | PCT | GB |
23 | 23 | .500 | ||
22 | 24 | .478 | 1.0 | |
22 | 25 | .468 | 1.5 | |
19 | 29 | .396 | 5.0 | |
16 | 31 | .340 | 7.5 |
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