Of all the guys I remember from my teen years, Gibson and Drysdale were the two guys whom you just didn't dig in against. I read somewhere that every game Gibby faced the Pirates, that he threw at Roberto Clemente at least once. And Clemente hated him for it. I was listening to the Cardinals radio broadcast, the night Roberto hit a liner back at Gibson, breaking his leg. I believe it was 1967. Not sure anybody could do that intentionally, but I believe Roberto would have, if he could.
Amazingly, Gibson pitched to three more batters, before collapsing on the mound with a broken shin bone.
A year later, in 1968, the rules greatly favored pitchers. They had raised the mound a year or two earlier to 15 inches and Gibson took full advantage. His ERA that season was 1.12 if I remember correctly. Pretty remarkable, by a remarkable man.
Rest in peace.