Star linebacker Clay Matthews left the Packers' 22-9 win over Detroit after the third quarter with a thumb injury.
Matthews sacked Matthew Stafford on the last play of the quarter on a third-and-9 at the 34 to push the Lions out of field-goal range. He jogged to the locker room with a trainer and did not return.
Matthews was coming back from a hamstring injury that knocked him out of a loss to the Bengals two weeks ago. His recovery was aided by a bye last week.
The pass-rushing specialist has three sacks this season.
The Packers also lost starting linebacker Brad Jones to a hamstring injury. His replacement, Robert Francois, later left the game with a torn Achilles.