Jennifer Wolff, the Life Skills Coordinator for the Cleveland Indians, was fixing up some things around her home on Friday morning. Suddenly, her “Women In Baseball” group chat—which includes 80 women working inside the game—started buzzing. News had broken that Kim Ng, a longtime baseball front office executive, was finally hired to run a team: the Miami Marlins made her the first woman team general manager in the history of a major North American men’s sports league. She felt elation, tinged with some frustration. “I was so incredibly excited and proud of Kim,” says Wolff, who worked under Ng (pronounced “ANG”) in the MLB front office in the early 2010s. “But then I also kind of thought, it’s about time.” Wolff laughs, a clear acknowledgment of both her happiness about the hire, and the ridiculous nature of the wait. “This is so well deserved,” she says. “But it should have happened years ago.” Ng, who will also become baseball’s first first Asian-American general man...