Since 1900, Jack Chesbro has the best ERA by a starting pitcher with 400.0+ innings pitched in a season, with an ERA of 1.82 in 1904.
| NAME | ERA | IP | SEASON | TM | 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 |  | J. Chesbro | 1.82 | 444.0 | 1904 |  NYH | 51 | 38 | 12 | .760 | 51 | 232 | 48 | 6 | 0 | 328 | 90 | 122 | 4 | 85 | 7 | 0 | 8 | 4.70 | 1.72 | 2.73 | 0.08 | 5.1 | 0.93 | .240 | 2.47 | 6.65 | |||
| 2 | | V. Willis | 2.20 | 404.2 | 1902 |  BSN | 46 | 26 | 19 | .578 | 46 | 227 | 45 | 4 | 0 | 368 | 99 | 139 | 6 | 101 | 13 | 0 | 13 | 5.05 | 2.25 | 2.25 | 0.13 | 6.2 | 1.16 | .284 | 3.09 | 8.18 |
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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