The Detroit Lions have lost another starter to concussion protocol days before their Thanksgiving game with the Buffalo Bills.
Left guard Jonah Jackson did not practice Tuesday for a second straight day and is unlikely to play Thursday because of a brain injury.
Jackson was designated as a non-participant on the Lions' estimated practice report Monday because of an illness. On Tuesday, his designation was changed to out with a concussion.
The Lions will be without top cornerback Jeff Okudah against the Bills after he sustained a brain injury in a collision with teammate Will Harris in the second quarter of last week's win over the New York Giants.