One morning this spring, Garrett Richards leaned back in a chair as he outlined the physical maturation and innate brilliance of one of his closest friends. The same day Richards became the 42nd overall selection in the 2009 draft, a teenager from the far side of the country slid to the Los Angeles Angels, near the end of the first round. At the time, he weighed less than 200 pounds. The fearsome power he would flaunt for summers to come had not yet roared to the surface.



“The thing about Mike,” Richards said, “is he made the adjustments faster than anybody else.”



By mid-2011, Mike Trout had soared into the majors as a 19-year-old. By the conclusion of the following season, he was the American League Rookie of the Year and, in a metaphorical sense, a snowball barreling down a slope. On Saturday in Boston, Trout cranked a high drive over the Green Monster and furthered his reputation as the most uncommon of talents. In this, his ninth season,...