Morel (oblique) will begin a rehab assignment with Triple-A Jacksonville on Tuesday, Christina De Nicola of MLB.com reports.
Morel is set to play five innings at first base in what will be his first game action since he went down with a left oblique strain in late March. He'll need a handful of rehab contests before rejoining the Marlins' active roster. Morel was slated to be Miami's primary first baseman before getting hurt.