Gillick joined the front office of the Houston Astros in 1976. He was soon promoted to the role of general manager and helped to rebuild the Astros into a competitive team. He made a number of trades and signings during his tenure, including the acquisition of future Hall of Famer Nolan Ryan. He also developed a strong farm system that produced young stars such as Craig Biggio and Jeff Bagwell. Gillick's Astros won the National League West Division title in 1986.
Gillick moved on to the Toronto Blue Jays in 1977. He quickly built the Blue Jays into a powerhouse. He acquired stars such as Dave Stieb, George Bell, and Roberto Alomar, and signed free agents such as Jack Morris and Dave Winfield. The Blue Jays won the American League East Division title five times under Gillick, culminating in consecutive World Series titles in 1992 and 1993.
Gillick then moved on to the Baltimore Orioles in 1996. He was instrumental in the Orioles' success, assembling a team that won the American League East Division title in 1997 and the American League Championship Series in 1997 and 1998. He also acquired future stars such as Mike Mussina and Albert Belle.
Gillick's final stop in Major League Baseball was with the Seattle Mariners. He was hired in 2000 and immediately set about rebuilding the team. He acquired stars such as Ichiro Suzuki and Bret Boone and signed free agents such as Edgar Martinez and Mike Cameron. The team won the American League West Division title in 2001.
Gillick retired from Major League Baseball in 2015, but he left behind a legacy of success. He is a three-time Executive of the Year, a member of the National Baseball Hall of Fame, and one of the most successful general managers in the history of the game.
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