O'Malley was optioned to Triple-A Tacoma on Sunday, Shannon Drayer of 710 AM ESPN Seattle reports.
O'Malley came up short in his efforts to win a spot as a super-utility man out of spring training, despite batting an impressive .471 and stealing five bases over 41 plate appearances in Cactus League play. It may take an injury to one of the Mariners' infielders before O'Malley gets called up to the big club.