Margevicius signed a contract with the TSG Hawks of the Chinese Professional Baseball League in Taiwan on Monday.
Margevicius was released by the Mariners on Monday.
Margevicius cleared waivers and was outrighted to Triple-A Tacoma on Monday.
The Mariners designated Margevicius for assignment Thursday, Daniel Kramer of MLB.com reports.
Margevicius was optioned to Triple-A Tacoma.
Margevicius (shoulder) has logged one Cactus League appearance this spring, allowing two earned runs on three hits over an inning while recording a strikeout against the Cubs on March 22.
Margevicius (shoulder) underwent thoracic outlet syndrome surgery earlier this summer, MLB.com reports.
Margevicius was transferred to the 60-day injured list due to thoracic outlet syndrome Thursday.
Margevicius was placed on the 10-day injured list with left shoulder inflammation Monday.
Margevicius dropped to 0-2 after he gave up four earned runs on two hits and a walk while retiring just one batter in Sunday's 5-3 loss to the Red Sox. Mariners manager Scott Servais said after the contest that Margevicius dealt with left shoulder fatigue during the outing, Corey Brock of The Athletic reports.