Green Bay quarterback Aaron Rodgers left the Packers' Sunday night game against the visiting Chicago Bears five minutes into the second quarter due to a left leg injury.
After he was taken to the medical tent to be evaluated, Rodgers was carted to the locker room as backup DeShone Kizer jogged onto the field with Green Bay trailing 10-0.
Kizer fumbled the ball, which was recovered by outside linebacker Khalil Mack on a strip sack, to end his first possession.
Rodgers attempted to get on his feet following a sack but crouched to the turf, grasping the back of his left leg.
Rodgers, who missed nine games last season because of a broken collarbone, recently signed a record four-year, $134 million extensions with $100 million in guarantees.