The Mariners outrighted Vosler to Triple-A Tacoma on Wednesday.
The Mariners designated Vosler for assignment on Monday.
Vosler was optioned to Triple-A Tacoma on Thursday.
Vosler will start at first base and bat seventh in Monday's game against the Red Sox.
Vosler went 1-for-5 with a two-run single in a win over the White Sox on Friday.
Vosler slotted in at designated hitter in Tuesday's 5-1 loss to the Angels and went 1-for-3 with a double, a walk and a run.
The Mariners selected Vosler's contract from Triple-A Tacoma on Monday.
Vosler signed a minor-league contract with the Mariners on Saturday.
Vosler elected to become a free agent Tuesday, Charlie Goldsmith of The Cincinnati Enquirer reports.
Vosler cleared waivers and was outrighted to Triple-A Louisville on Thursday.