Brook Jacoby's journey in Major League Baseball began when he was drafted by the Atlanta Braves in the seventh round of the 1979 amateur draft. He made his MLB debut with the Braves in 1981, marking the start of a career that would see him become a reliable third baseman. Although his time with the Braves was brief, it set the stage for his future in the league.

In 1983, Jacoby was traded to the Cleveland Indians, a move that would define the majority of his professional career. With the Indians, he found a more permanent home and became a regular fixture at third base. Jacoby's tenure with Cleveland spanned nearly a decade, during which he became known for his steady defensive skills and consistent batting performance.

Jacoby's best seasons came in the mid-1980s. In 1987, he achieved a career-high batting average of .300, along with 32 home runs and 69 RBIs, earning him a spot on the American League All-Star team. This performance was a highlight in a period where he was considered one of the more reliable players on the Indians' roster. He repeated his All-Star appearance in 1990, further solidifying his reputation as a dependable player.

Throughout his career with the Indians, Jacoby was known for his work ethic and ability to perform under pressure. His defensive skills at third base were complemented by his offensive contributions, making him a valuable player for the team. Despite the Indians' struggles during much of his tenure, Jacoby remained a consistent presence in the lineup.

In 1991, Jacoby was traded to the Oakland Athletics, where he played for a single season. His time with the Athletics was short-lived, and he returned to the Indians in 1992 for his final season in Major League Baseball. After retiring as a player, Jacoby transitioned into coaching, sharing his experience and knowledge of the game with younger players.