On rehab assignment, Ramos threw one inning at Double-A Jacksonville on Monday. At Marlins Park on Thursday, the righty faced hitters in a simulated game.
As Ramos is coming off the disabled list, the club made a corresponding roster move, placing reliever Kevin Gregg on the DL with right elbow inflammation.
In nine innings this season, Gregg's ERA is 10.00. The veteran gave up three earned runs without recording an out on Sunday against the Mets at Citi Field.
"He came in and said it was bothering him for a few days before the All-Star break," Marlins manager Mike Redmond said. "Knowing we were going to have this coming up with A.J. being ready to go, it seemed like the right decision to make.
"We'll give Kevin a few days off and let him be 100 percent."
Ramos will slide back into a late-inning setup role for closer Steve Cishek. Ramos has appeared in 39 games, and he has an ERA of 2.17.
"We were using him a lot," Redmond said. "He needed time off to get himself back to 100 percent. Hopefully this will carry him through the rest of the season."
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter