Jack Aker vs. George O'Donnell — Career Comparison

George O'Donnell built a career as a starting pitcher and Jack Aker as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Jack Aker posted stronger surface numbers — ERA 3.28 and WHIP 1.369 compared to 4.53 and 1.443 for George O'Donnell. By the career numbers, Jack Aker had the better of this cross-role comparison — though era context would sharpen the verdict.