In Chicago, Marmol compiled 117 saves in 145 opportunities. They weren't always a thing of beauty.
Command issues have persisted, which led to him being traded to the Dodgers last year.
In 52 games overall, the right-hander was 2-4 with a 4.41 ERA, while converting two of five save chances.
Walks were an issue as he put 40 on base in 49 innings.
When around the plate, Marmol's stuff can be electric. He struck out 59.
"That is in the past," Marmol said. "I don't even think about it anymore. I'm here with a new team. I'm trying to do the best I can right now. This is a big chance for me to try to help the team."
Marmol, who signed for $1.25 million, projects as a late-inning setup option for closer Steve Cishek.
For a seventh- or eighth-inning spot, he joins right-handers A.J. Ramos, Carter Capps, along with lefty Mike Dunn.
"It's one of those things where everybody talks about. They ask where are you going to use him, in what situation?" manager Mike Redmond said. "I told a lot of those bullpen guys, it's really up to them, and how they pitch. The key for him is pounding the strike zone, throwing strikes, and getting strikes. If he's about to do that and is effective, then he will be one of the guys who will be an option for us late in the game."
The walks and wildness have surfaced throughout his career. Part of the problem last year was Marmol didn't have a consistent arm slot.
"It was a lot of things," Marmol said. "My mechanics, and my stuff. What can I say, it was a bad year. When you have a bad year, anything can happen."
Marmol pitched more effectively in winter ball in the Dominican Republic, and he participated in the Caribbean Series, which caught the Marlins' attention.
"It helped me a lot," Marmol said of pitching in the winter. "It helped with my mechanics. I feel great. This is a new team. I'm trying to do the best I can."