Guaipe is available when the Mariners play the Colorado Rockies on Tuesday night.
Guaipe was 0-4 with a 3.02 ERA 34 appearances with Tacoma, including a 1.42 ERA in his last 15 appearances with the Rainiers. He is 0-2 with an 8.31 ERA in two previous stints with Seattle.
Ramirez was acquired from the New York Yankees on Thursday and recalled from Tacoma a day later. He did not appear in a game for the Mariners.
He had a 15.00 ERA in three games with the Yankees this season.