To make room on the roster, reliever Lucas Luetge was sent down to Seattle's top farm club.
It is Ramirez's 13th start of the season with the Mariners. He began the day with a 1-5 record and a 4.35 ERA.
Luetge did not appear in a game for the Mariners after being recalled from Tacoma on Friday. Luetge has a 5.40 ERA in four major league appearances this season.