Marshall has been active during pre-season but is in a battle to be fit for the first week of the regular season after undergoing hip surgery in the off-season.
"It's one of those things where I'm just trying to get healthy for Week 1," Marshall told the Chicago Sun-Times.
"So you've got to have a game plan coming off surgery, a third hip surgery. So yeah, I'm not where I want to be right now. It's a little frustrating. But we'll see."
Chicago open the season against the Cincinnati Bengals on September 8.