Paul Splittorff had the best ERA when pitching at least 40 innings in April 1978, with an ERA of 1.79.
| NAME | ERA | IP | MONTH | G | W | L | W% | GS | SO | CG | SHO | SV | H | ER | R | HR | BB | HBP | GF | IBB | TBF | WP | K/9 | BB/9 | K/BB | HR/9 | K% | BB% | WHIP | BABIP | RA | H/9 | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 |  | P. Splittorff | 1.79 | 40.1 | April 1978 | 5 | 4 | 1 | .800 | 5 | 10 | 2 | 1 | 0 | 26 | 8 | 8 | 4 | 7 | 1 | 0 | 0 | 151 | 0 | 2.23 | 1.56 | 1.43 | 0.89 | 6.6 | 4.6 | 0.82 | .171 | 1.79 | 5.80 |
| 2 |  | N. Ryan | 1.98 | 41.0 | April 1978 | 5 | 1 | 1 | .500 | 5 | 59 | 1 | 1 | 0 | 19 | 9 | 10 | 1 | 25 | 1 | 0 | 0 | 164 | 5 | 12.95 | 5.49 | 2.36 | 0.22 | 36.0 | 15.2 | 1.07 | .231 | 2.20 | 4.17 |
| 3 |  | B. Lee | 2.25 | 40.0 | April 1978 | 5 | 4 | 0 | 1.000 | 5 | 12 | 2 | 1 | 0 | 37 | 10 | 12 | 6 | 6 | 0 | 0 | 0 | 155 | 0 | 2.70 | 1.35 | 2.00 | 1.35 | 7.7 | 3.9 | 1.08 | .237 | 2.70 | 8.33 |
| 4 |  | F. Tanana | 2.45 | 40.1 | April 1978 | 5 | 5 | 0 | 1.000 | 5 | 17 | 2 | 1 | 0 | 43 | 11 | 11 | 4 | 7 | 1 | 0 | 1 | 169 | 0 | 3.79 | 1.56 | 2.43 | 0.89 | 10.1 | 4.1 | 1.24 | .279 | 2.45 | 9.60 |
| 5 |  | P. Niekro | 2.66 | 44.0 | April 1978 | 6 | 2 | 4 | .333 | 6 | 37 | 4 | 1 | 0 | 32 | 13 | 18 | 1 | 19 | 1 | 0 | 1 | 178 | 2 | 7.57 | 3.89 | 1.95 | 0.20 | 20.8 | 10.7 | 1.16 | .258 | 3.68 | 6.55 |
| 6 | | D. Leonard | 3.11 | 46.1 | April 1978 | 6 | 3 | 3 | .500 | 6 | 31 | 4 | 0 | 0 | 47 | 16 | 19 | 7 | 14 | 1 | 0 | 0 | 198 | 4 | 6.02 | 2.72 | 2.21 | 1.36 | 15.7 | 7.1 | 1.32 | .276 | 3.69 | 9.13 |
| 7 |  | R. Erickson | 3.86 | 42.0 | April 1978 | 6 | 2 | 2 | .500 | 6 | 23 | 1 | 0 | 0 | 40 | 18 | 22 | 1 | 13 | 2 | 0 | 0 | 178 | 4 | 4.93 | 2.79 | 1.77 | 0.21 | 12.9 | 7.3 | 1.26 | .281 | 4.71 | 8.57 |
StatMuse has game-level data for ERA 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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