The Marlins recalled Tarnok from Triple-A Jacksonville on Sunday.
Miami had optioned Tarnok to Triple-A on Thursday, but he'll rejoin the big club just three days later after Ryan Gusto (shoulder) was placed on the injured list in a corresponding move. Tarnok has made three appearances out of the Marlins bullpen this season, covering 4.1 innings while allowing two earned runs on one hit and two walks.