Latos, who's been sidelined since May 23 with left knee inflammation, looked sharp in his latest rehab outing for Triple-A New Orleans, allowing three hits and striking out four in 4 1/3 innings Monday night.
"He felt strong, his [velocity] certainly indicated that," Jennings said Tuesday. "He had some of the best, if not the best, velocity we've seen all year. [Pitching coach] Chuck [Hernandez] and I called the Triple-A pitching coach, John Duffy, just to get his assessment of it."
Latos had been showing signs of turning his season around prior to landing on the DL, notching a pair of quality starts to begin the month before laboring through his next two outings with knee pain. The 27-year-old is 1-4 with a 6.12 ERA in nine starts.
Jennings said Latos will replace left-hander Brad Hand in the rotation, with Dan Haren scheduled to pitch on normal rest in Sunday's series finale against Colorado.
The Marlins remain optimistic Jarred Cosart (vertigo) is also close to returning, while Jose Fernandez continues to make progress in his recovery from Tommy John surgery. Jennings said last week that right-hander Henderson Alvarez (shoulder) is still on a no-throw status.
Dan Toman is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.