We are in a historic era for the home run. The 2017 season saw the most homers ever, with 2016 and 2018 close behind, a shift that has transformed the way the game is played. In Swing Kings, Wall Street Journal national baseball writer Jared Diamond reveals that the secret behind this unprecedented shift isn't steroids or the stitching of the baseballs, it's the most elemental explanation of all: the swing. In this lively narrative romp, he tracks a group of baseball's biggest stars— including Aaron Judge and J.D. Martinez— who remade their swings under the tutelage of a band of renegade coaches, and remade the game of baseball in the process. These coaches, many of them baseball washouts who have reinvented themselves as swing gurus, for years were one of the game's best-kept secrets. Now, as Diamond artfully charts, they're moving from the baseball margins to its center of power. They are changing the way hitting is taught to players of all ages, and major league clubs are scrambling for their services, hiring them in record numbers as coaches and consultants. Diamond himself, taking a page out of the George Plimpton playbook, enlisted the tutelage of each swing coach he profiles, with an aim toward starring in the annual Boston-New York media game at Yankee Stadium. Swing Kings is both a rollicking history of baseball's recent past and a deeply reported, character-driven account of a battle between opponents as old as time: old and new, change and stasis, the establishment and those who break from it. For fans of the game, old and young, and for readers of The Arm, Astroball, and of course Moneyball, Swing Kings is the next big book on America's pastime.