He’s mixing three pitches – a mid 90s fastball, a hard biting slider, and a surprisingly good change-up. He’s been good against both left-handed and right-handed hitters. He’s throwing strikes, getting ahead in counts, and forcing hitters to chase nasty breaking balls in the dirt. … It’s a testament to how much improvement he made in spring training, the skills of White Sox pitching coach Don Cooper, and, truthfully, how very easy it is to be a relief pitcher if you have a good arm. And Sergio Santos has a very, very good arm.