The Rays selected Ramirez's contract from Triple-A Durham on Monday.
Ramirez will begin his second stint with the Rays of the season, as he was previously called up from Triple-A on April 20 and produced a 4.50 ERA and 1.06 WHIP over 16 innings before being cast off the 40-man roster about a month later. The Rays optioned lefty Jacob Lopez to Triple-A in a corresponding move to clear a spot on the active roster for Ramirez, who will likely fill a multi-inning role out of the bullpen.