1. Santiago Casilla has been very, very good over the past three years. Rk Player ERA+ IP 1 Mariano Rivera 233 129.2 2 Craig Kimbrel 230 122.2 3 Scott Downs 226 136.2 4 Sergio Romo 222 128.0 5 Santiago Casilla 212 133.1 Provided by Baseball-Reference.com: View Play Index Tool Used Generated 6/16/2012. That’s the top-five ERA+ ranking for relievers that… Read more →