What it means is Slowey, who finished the season on the 60-day disabled list, has accepted the fact he will once again have to earn his spot on the roster.
As a non-roster invitee this season, Slowey opened as Miami's No. 2 starter. He made 14 starts and appeared in 20 games, going 3-6 with a 3.86 ERA in 92 innings.
But on July 28, he was placed on the 15-day disabled list with right forearm discomfort. On Sept. 1, he was transferred to the 60-day disabled list.
Slowey, who was a teammate of Miami manager Mike Redmond in Minnesota, said he felt he had some unfinished business with the Marlins.
"Absolutely, I feel like not only do I have unfinished business here, I'd love to be here," Slowey said in an interview on the last day of the season. "If it's something that works out for them, this is where I want to be. I love the on-field staff. I love the guys in the clubhouse.
"Next year is going to be a lot of fun with these guys. These guys have got their feet wet, these guys understand what they've got to do in order to win in the big leagues. I think there is a lot of talent in this room. I'd like to be part of it going forward."
Slowey was arbitration eligible, but because he is no longer on the 40-man roster, he will not be going through the process.
Along with Slowey, the Marlins also outrighted right-handers Jose Ceda and Steven Ames, first baseman Joe Mahoney, catcher Koyie Hill, infielder Gil Velazquez and lefty Zach Phillips.
Before the season ended, Slowey threw two bullpen sessions in Miami. He said both went well.
"The first one, you're always a little tentative, a little hesitant," Slowey said. "The first one felt great. The second one, it felt awesome."