Stan Musial, who died Jan. 19 at the age of 92, was one of the greatest ballplayers in major league history. But his singular genius as an athlete derived not from an incandescent passion or from a talent for highlight-reel-worthy drama--although to be sure, he had his share of late-inning heroics and jaw-dropping performances. Instead, Musial's magnificence, and a key reason he was so beloved for so long, was rooted in his uncanny, unwavering, crazily consistent excellence across decades.
Musial played every game of his 22-year career with the St. Louis Cardinals. In his first, on Sept. 17, 1941, the 20-year-old...