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The 1989 Seattle Mariners season was their 13th since the franchise creation, and the team finished sixth in the American League West, with a record of 73–89 (.451). The Mariners were led by first-year manager Jim Lefebvre and the season was enlivened by the arrival of nineteen-year-old Ken Griffey Jr., the first overall pick of the 1987 draft.
Offseason
November 15, 1988: Luis DeLeón was signed as a free agent by the Mariners.
In spring training, Ken Griffey Jr. set preseason team records for hits (32), RBIs (20) and total bases (49).
Regular season
Ken Griffey Jr. made his major league baseball debut on opening day, April 3, against the defending American League champion Oakland Athletics. Griffey hit a double in his first at-bat. During the 1989 season, Griffey was honored by being selected as card number one in the 1989 Upper Deck baseball card set.
The Mariners had the lowest payroll in the majors in 1989, at $7.6 million.
^ Mint Condition: How Baseball Cards Became an American Obsession, p.167, Dave Jamieson, 2010, Atlantic Monthly Press, imprint of Grove/Atlantic Inc., New York, ISBN978-0-8021-1939-1
Johnson, Lloyd, and Wolff, Miles, ed., The Encyclopedia of Minor League Baseball, 2nd and 3rd editions. Durham, North Carolina: Baseball America, 1997 and 2007