Sounds to me like he may be trying to rush it.
http://www.cbs.sportsline.com/nfl/story/9611206CINCINNATI -- Carson Palmer said Sunday he expects to play in the Cincinnati Bengals' preseason game next Monday against Green Bay, provided he doesn't have any swelling this week in his surgically rebuilt knee.
Coach Marvin Lewis was noncommittal earlier about when his starting quarterback would get on the field for the first time. Later, Palmer said he plans to be under center against the Packers.
"I'm preparing to play. I'm practicing to play," Palmer said. "That's been part of the plan, part of the schedule. I'll see how I feel later in the week, but right now I'm expecting to play."
Palmer said he's had a little bit of swelling in the left knee, which was severely damaged during the Bengals' playoff loss to Pittsburgh in January. He has been working out during training camp without a significant setback, but didn't play in either of the first two preseason games.
"The thing we keep worrying about is swelling," Palmer said. "That's one of the things we need to worry about. As long as we don't have a bunch of swelling and tenderness, I'll be ready to roll."