Bellatti's contract was selected by the Marlins on Monday.
The 29-year-old has 23.1 innings of big-league experience under his belt, all of which came back in 2015 for the Rays. He's thrown 10 innings for Triple-A Jacksonville this season, allowing three runs while striking out 12 batters. He'll likely serve in a low-leverage role during his time in the majors.