Seattle made the move with Morrison before Wednesday night's game and immediately placed him in the starting lineup. The Mariners put first baseman Justin Smoak on the 15-day disabled list with a strained left quadriceps, retroactive to June 10.
Morrison has been out since April 14 when he left a game in Texas with a strained hamstring. Morrison spent the past 18 games on a rehab assignment at Triple-A Tacoma where he hit .308 with three homers.
Smoak has been bothered by the quad for a couple of weeks. The switch-hitter says hitting isn't causing problems but running is where he is limited. Smoak is hitting .208.