After Thursday night's 8-3 loss to the Padres at Petco Park, Mattingly announced that Kyle Barraclough will take over the ninth-inning role.
"We feel like [Barraclough] had earned that with the way he has thrown the ball," Mattingly said. "This is his chance to show he can be that guy."
Ziegler on Wednesday night allowed two runs, with one unearned, and suffered his first blown save in Miami's 3-2 loss to the Padres at Petco Park.
The 38-year-old converted 9 of 10 save chances, and has 104 saves in his career. For the most part, he's been effective in close situations, but he's also had rough outings, and his ERA is 7.83 in 23 innings, as he's allowed 20 earned runs.
"Zieg understands the situation," Mattingly said before the series finale at San Diego. "I just told him we were going to make a change and try to do things a little differently."
Barraclough, 28, has one save this season and two in his career. The right-hander has been effective in setup situations, posting a 1.48 ERA in 24 1/3 innings. He has a 9.99 strikeouts per nine innings, and a WHIP of 0.99.
Ziegler's WHIP is 1.74, and the submarine-style righty has allowed 13 runs in his last 13 1/3 innings, with a 5.87 strikeouts per nine innings.
With a young roster, the Marlins will be experimenting with roles. Mattingly says Barraclough and Drew Steckenrider have closer potential.
"In general, everyone would love to have that guy like Kenley Jansen or whoever, you know, who could be throwing multiple innings out there," Mattingly said, referring to the Dodgers' closer.
The Padres use lefty Brad Hand, who has the ability to work multiple innings.
"The way [the Padres] use Hand, here," Mattingly said. "He may throw two innings. You want a someone you can say against the toughest part of the order, this is a guy I want to be using."
A consummate professional, Ziegler expressed his frustration Wednesday night after the loss.
"It's pretty empty," he said. "It's a lot of self-examination and questioning what is going on. This is my 11th season. I've never had a stretch like this, really. It's frustrating, for sure."
The Marlins could spend the rest of the season experimenting with late-innings options. Tayron Guerrero is the hardest thrower in the bullpen, but he's struggled lately with command.
Lefty Adam Conley has converted from the rotation to the bullpen, and is in the mix for high-leverage situations.
"I think you want to find multiple guys who can handle the back end of the game," Mattingly said. "There are different guys in that conversation that have the stuff, you think, to do that."
Closers usually aren't appointed, they secure the roles by performance.
"Different things like the personality to handle the end of the game," Mattingly noted. "People probably don't put anything into that, but we've seen it over the years, you put the wrong personality out there in that role, and it doesn't seem to go that well, no matter how good the stuff is."