Mark Prior vs. Roberto Rivera — Career Comparison

Mark Prior built a career as a starting pitcher and Roberto Rivera as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Mark Prior posted stronger surface numbers — ERA 3.51 and WHIP 1.240 compared to 4.5 and 1.583 for Roberto Rivera. By the career numbers, Mark Prior had the better of this cross-role comparison — though era context would sharpen the verdict.