Now, he's declaring that Fairley, the defensive tackle who was Detroit's first-round pick in 2011, is definitively working with the second team.
"If you're asking me whether or not Fairley is going to be a starter, he's not starting right now," Caldwell said Monday. "He's second team.
"But the rest of it, we'll look. It's a long week. We've got a lot of work to do in between and typically like most games, we'll take a look at where we are and make an assessment on that toward the end of the week."
Fairley started the first preseason game against Cleveland but was demoted last week in favor of 10-year veteran C.J. Mosley. Fairley played 15 snaps against Oakland on Friday night, the fewest of any Lions defensive tackle. In those snaps, he made one tackle but was often pushed off the ball.
On Saturday, Caldwell said Fairley "played better" against the Raiders, although he didn't go into more specifics. Fairley declined to comment to the media Saturday, saying "not today."
On Monday, he was not in the Detroit locker room during media access.
The Lions declined the fifth-year option on Fairley during the offseason. At the time, general manager Martin Mayhew said it was in part to try to motivate Fairley, who has struggled with consistency throughout his career.
He showed up at spring workouts in good shape and under 300 pounds. By training camp, he was about 305 pounds, but Caldwell indicated Fairley was within an acceptable weight range. Last week, Caldwell said Fairley is trying to find a comfortable playing weight.