Jack Aker career ERA
3.28Career Regular Season
Jack Aker has a career ERA of 3.28 over 11 regular seasons.
| GP: Games the player appeared in, however briefly. | W: Games in which this pitcher was credited with the win. | L: Games in which this pitcher was charged with the loss. | ERA: Earned runs allowed per nine innings pitched — lower is better. Under 3.00 is excellent. | IP: Innings pitched. The decimal counts outs, so 6.2 is six innings and two more outs. | K: Batters this pitcher struck out. | BB: Times the batter reached first base on four balls. | WHIP: Walks and hits allowed per inning pitched — lower is better. Around 1.00 is elite. | SV: Games finished by protecting a narrow lead to the last out. | ||
|---|---|---|---|---|---|---|---|---|---|---|
| 1964 |  ATH | 9 | 0 | 1 | 8.82 | 16.1 | 7 | 10 | 1.65 | 0 |
| 1965 | ATH | 34 | 4 | 3 | 3.16 | 51.1 | 26 | 18 | 1.23 | 3 |
| 1966 | ATH | 66 | 8 | 4 | 1.99 | 113.0 | 68 | 28 | 0.96 | 32 |
| 1967 | ATH | 57 | 3 | 8 | 4.30 | 88.0 | 65 | 32 | 1.35 | 12 |
| 1968 | ATH | 54 | 4 | 4 | 4.10 | 74.2 | 44 | 33 | 1.41 | 11 |
| 1969 |  MIL/NYY | 53 | 8 | 6 | 3.17 | 82.1 | 47 | 35 | 1.35 | 14 |
| 1970 | NYY | 41 | 4 | 2 | 2.06 | 70.0 | 36 | 20 | 1.10 | 16 |
| 1971 | NYY | 41 | 4 | 4 | 2.59 | 55.2 | 24 | 26 | 1.33 | 4 |
| 1972 |  NYY/CHC | 52 | 6 | 6 | 2.96 | 73.0 | 37 | 26 | 1.32 | 17 |
| 1973 | CHC | 47 | 4 | 5 | 4.10 | 63.2 | 25 | 23 | 1.55 | 12 |
| 1974 |  ATL/NYM | 41 | 2 | 2 | 3.57 | 58.0 | 25 | 23 | 1.26 | 2 |
What the columns mean: W · L · ERA · IP · K · BB · WHIP · SV
- Best season on file: 1.99 in 1966.
- Most recent: 3.57 in 1974.
Average of 11 regular seasons, 1964 through 1974. Figures come from ESPN's box scores and were last read on October 24, 2026.