The Mariners did not have a full-time designated hitter in their inaugural season. Juan Bernhardt, Steve Braun, Dave Collins, and Leroy Stanton split time at DH. Bernhardt was with the Mariners for two seasons before being traded to the Chicago White Sox. In 1978 he had to play in Triple-A well as with the Mariners. He played first and third base that season after only being a DH in 1977. The Mariners picked him up from the New York Yankees in the expansion draft.
Braun played mostly in left field though he DH’d for 31 games.