Graves is competing for one of the Marlins' final three rotation spots in spring training, Joe Frisaro of MLB.com reports.
Graves was selected by the Marlins in last year's Rule 5 draft, so he'll have to stick on the team's active roster all season, otherwise he'll be exposed to waivers and offered back to the Athletics. That said, Miami will give him a look during spring, though seeing as the 25-year-old hasn't pitched above Double-A -- and owns a rough 5.97 ERA and 1.83 WHIP across 31.2 innings there -- he'll likely settle for a low-leverage bullpen role.