Morse is batting .161 in his last 14 games since returning from the disabled list following a month-long issue with a strained hamstring. On the Mariners' current road trip, Morse has hit just 2-for-16.
Michael Saunders started in right field on Monday.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. Jeff Kirshman is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.