The Tigers optioned Manning to Triple-A Toledo on Tuesday, Evan Woodbery of MLive.com reports.
Manning pitched two scoreless innings in Wednesday Grapefruit League game against the Phillies. He allowed one hit and struck out one.
Manning will make his Grapefruit League debut Wednesday, pitching after Daniel Norris, Jason Beck of MLB.com reports.
Manning had his contract selected by the Tigers on Friday.
Manning said Tuesday that he feels 100 percent after recovering from a minor forearm issue over the summer, Cody Stavenhagen of The Athletic reports.
Manning has been shut down for the remainder of the season with a right forearm strain, Chris McCosky of The Detroit News reports.
General manager Al Avila said Manning needs to continue developing his command, control and make mechanical tweaks at the Tigers' alternate training site, Evan Petzold of the Detroit Free Press reports. "It's a little bit longer with him now," Avila said Monday.
Manning was reassigned to the Tigers' alternate training site Monday.
Manning will be a part of the Tigers' 60-man player pool this season.
Manning will likely be on the Tigers' 20-man taxi squad when the regular season gets underway, Anthony Fenech of the Detroit Free Press reports.