The Marlins will begin the 2020 season with a variety of options available for the rotation. Spring Training remains to be played, and free agency is never really done, but we can kind of suss out what the Opening Day rotation will look like in 89 more days.
Being on the 40-man roster is no guarantee that a player will break camp with the parent club. Not being on the 40-man roster makes the odds longer, but players have surprised before. Jon Berti was the latest non-roster invitee to flourish after a strong spring.