Lou Gehrig had the worst season of his career in 1938. He finished the year with 29 home runs and drove in 114 runs, in the American League’s top 10 in both categories. And, of course, he played every game. Those were great numbers for most people. But Gehrig wasn’t most people. He was The Iron Horse. He was Larrupin’ Lou. Since 1927, he had averaged .350 with almost 40 homers and more than 150 RBIs. These 1938 totals were just not good enough. Not for Gehrig. He found himself mired in a season-long slump, where the ball just didn’t...