Jack Mercer vs. Robin Roberts — Career Comparison

Robin Roberts built a career as a starting pitcher and Jack Mercer as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Jack Mercer posted stronger surface numbers — ERA 0 and WHIP 2.000 compared to 3.41 and 1.184 for Robin Roberts. By the career numbers, Jack Mercer had the better of this cross-role comparison — though era context would sharpen the verdict.