Carr had been listed as probable after practicing Friday, but he experienced pain on the flight later that night. He was downgraded before the team's afternoon walkthrough Saturday afternoon. Carr is expected to warm up today to determine if he'll play.
If he can't go, coach John Fox will have to decide between 43-year-old Vinny Testaverde or undrafted rookie Matt Moore.
Testaverde was signed Wednesday and has been scrambling to learn the offense and his new teammates. Moore was signed last month after being cut by Dallas, and acknowledged he's been a bit overwhelmed working with the first team in practice.
Carr had replaced Jake Delhomme, who will undergo season-ending elbow surgery.
FALCONS: Waived defensive end Josh Mallard and signed linebacker Travis Williams from the practice squad.
Mallard, a three-year veteran out of Georgia, had four sacks and 11 tackles in 14 games for Atlanta last season. He made one start last year but did not have a tackle this season.
Williams (6-foot-1, 224) signed with Atlanta as an undrafted free agent last year and re-signed with team on Jan. 10.
Depth at linebacker is a concern for Monday night's game against the New York Giants at the Georgia Dome.
Stephen Nicholas is out with an ankle injury and Keith Brooking is questionable with a hamstring injury.
- The NFL has fined Tennessee Titans defensive end Kyle Vanden Bosch $7,500 for a low hit on Atlanta quarterback Joey Harrington.
Vanden Bosch told The Tennessean that he plans to appeal the fine.