Book excerpt: A fascinating look inside the inner sanctum of the Steinbrenner era Yankees No team in American sports has as storied a history as the New York Yankees, winners of 27 World Series. As the strength and conditioning coach for the Yankees for parts of three decades, Jeff Mangold?was firmly embedded ?in building the dynasty of the 1990s and 2000s.? In?Power and Pinstripes, Mangold shares priceless stories from his 14 seasons behind the scenes in the Bronx. Mangold had a front-row seat to the daily drama of George Steinbrenner's revolving door of managers—Yogi Berra, Billy Martin, and Lou Piniella—in the 1980s. Then, when he returned to the Yankees in 1998, he joined a juggernaut of a team and was tasked with maintaining the health of a star-studded roster including the Core Four of Derek Jeter, Jorge Posada, Andy?Pettitte, and Mariano Rivera.? Mangold shares personal tales of finding his way with stars like Dave Winfield and Ron Guidry, motivating personalities like David Wells, and facing a thorny challenge that later became a scandal when Roger Clemens and other Yankees arrived at?spring training with their own personal strength coaches in tow.? Yankees fans will not want to miss this unique perspective on a the franchise during one of baseball's most exciting and controversial eras.