The Mariners recalled Speier from Triple-A Tacoma on Friday.
With Yimi Garcia (elbow) headed for the injured list, the Mariners will call upon Speier to replenish their bullpen depth. The 29-year-old southpaw has struggled in the big leagues this year, accumulating a 5.95 ERA and 1.42 WHIP over 19.2 innings. However, he's allowed just two earned runs over eight frames since being sent to Triple-A at the end of July.