Brandon Woodruff had the lowest WHIP when pitching at least 40 innings in a month in 2021, with a WHIP of 0.67 in May 2021.
| NAME | WHIP | IP | MONTH | G | W | L | W% | GS | ERA | SO | CG | SHO | SV | H | ER | R | HR | BB | HBP | GF | IBB | TBF | WP | K/9 | BB/9 | K/BB | HR/9 | K% | BB% | BABIP | RA | H/9 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | B. Woodruff | 0.67 | 42.0 | May 2021 | 6 | 2 | 2 | .500 | 6 | 1.07 | 49 | 0 | 0 | 0 | 20 | 5 | 6 | 3 | 8 | 2 | 0 | 0 | 153 | 1 | 10.50 | 1.71 | 6.13 | 0.64 | 32.0 | 5.2 | .187 | 1.29 | 4.29 |
| 2 |  | T. Bauer | 0.68 | 40.0 | April 2021 | 6 | 3 | 1 | .750 | 6 | 2.48 | 51 | 1 | 0 | 0 | 19 | 11 | 12 | 7 | 8 | 2 | 0 | 0 | 148 | 1 | 11.48 | 1.80 | 6.38 | 1.58 | 34.5 | 5.4 | .150 | 2.70 | 4.27 |
| 3 |  | M. Fried | 0.73 | 41.0 | September 2021 | 6 | 3 | 0 | 1.000 | 6 | 1.54 | 36 | 1 | 1 | 0 | 23 | 7 | 8 | 3 | 7 | 0 | 0 | 0 | 151 | 2 | 7.90 | 1.54 | 5.14 | 0.66 | 23.8 | 4.6 | .190 | 1.76 | 5.05 |
| 4 |  | G. Márquez | 0.76 | 41.0 | June 2021 | 6 | 4 | 1 | .800 | 6 | 2.41 | 32 | 1 | 1 | 0 | 22 | 11 | 12 | 1 | 9 | 2 | 0 | 0 | 153 | 3 | 7.02 | 1.98 | 3.56 | 0.22 | 20.9 | 5.9 | .193 | 2.63 | 4.83 |
| 5 |  | A. Wainwright | 0.80 | 44.0 | August 2021 | 6 | 5 | 1 | .833 | 6 | 1.43 | 36 | 1 | 1 | 0 | 29 | 7 | 7 | 1 | 6 | 1 | 0 | 0 | 164 | 0 | 7.36 | 1.23 | 6.00 | 0.20 | 22.0 | 3.7 | .233 | 1.43 | 5.93 |
| 6 |  | M. Gonzales | 0.80 | 40.0 | August 2021 | 6 | 3 | 0 | 1.000 | 6 | 1.58 | 27 | 1 | 0 | 0 | 26 | 7 | 7 | 5 | 6 | 0 | 0 | 0 | 147 | 0 | 6.08 | 1.35 | 4.50 | 1.13 | 18.4 | 4.1 | .193 | 1.58 | 5.85 |
| 7 |  | Z. Wheeler | 0.81 | 43.1 | May 2021 | 6 | 2 | 0 | 1.000 | 6 | 2.08 | 57 | 1 | 1 | 0 | 30 | 10 | 11 | 2 | 5 | 2 | 0 | 0 | 164 | 2 | 11.84 | 1.04 | 11.40 | 0.42 | 34.8 | 3.0 | .286 | 2.28 | 6.23 |
| 8 |  | R. Ray | 0.85 | 41.0 | August 2021 | 6 | 1 | 0 | 1.000 | 6 | 1.76 | 52 | 0 | 0 | 0 | 27 | 8 | 8 | 2 | 8 | 1 | 0 | 0 | 154 | 1 | 11.41 | 1.76 | 6.50 | 0.44 | 33.8 | 5.2 | .275 | 1.76 | 5.93 |
| 9 |  | W. Buehler | 0.97 | 40.1 | August 2021 | 6 | 2 | 1 | .667 | 6 | 1.56 | 44 | 0 | 0 | 0 | 26 | 7 | 8 | 3 | 13 | 1 | 0 | 1 | 161 | 3 | 9.82 | 2.90 | 3.38 | 0.67 | 27.3 | 8.1 | .230 | 1.79 | 5.80 |
| 10 |  | S. Bieber | 0.99 | 42.1 | April 2021 | 6 | 3 | 2 | .600 | 6 | 2.76 | 68 | 0 | 0 | 0 | 28 | 13 | 13 | 5 | 14 | 1 | 0 | 0 | 172 | 3 | 14.46 | 2.98 | 4.86 | 1.06 | 39.5 | 8.1 | .274 | 2.76 | 5.95 |
| 11 | | Z. Wheeler | 1.02 | 43.0 | August 2021 | 6 | 3 | 3 | .500 | 6 | 4.81 | 43 | 1 | 1 | 0 | 36 | 23 | 25 | 6 | 8 | 1 | 0 | 0 | 174 | 2 | 9.00 | 1.67 | 5.38 | 1.26 | 24.7 | 4.6 | .259 | 5.23 | 7.53 |
| 12 |  | S. Alcantara | 1.13 | 41.2 | June 2021 | 6 | 2 | 3 | .400 | 6 | 2.59 | 29 | 1 | 0 | 0 | 38 | 12 | 14 | 3 | 9 | 2 | 0 | 0 | 170 | 2 | 6.26 | 1.94 | 3.22 | 0.65 | 17.1 | 5.3 | .276 | 3.02 | 8.21 |
| 13 |  | A. Civale | 1.19 | 40.1 | May 2021 | 6 | 3 | 2 | .600 | 6 | 3.57 | 28 | 0 | 0 | 0 | 39 | 16 | 16 | 6 | 9 | 1 | 0 | 0 | 165 | 2 | 6.25 | 2.01 | 3.11 | 1.34 | 17.0 | 5.5 | .273 | 3.57 | 8.70 |
StatMuse has game-level data for WHIP 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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