The Cardinals placed quarterback Carson Palmer on injured reserve after the 37-year-old broke his left arm during Arizona's 33-0 loss to the Rams in London on Sunday.
The move means Palmer is not eligible to return until the Cardinals host the Giants in Week 17.
Palmer was replaced on Sunday by Drew Stanton, who went 5-14 for 62 yards and an interception. Stanton will start this Sunday when Arizona plays at the 49ers, and Blaine Gabbert will serve as the backup.
Palmer joins star running back David Johnson on injured reserve. Johnson is technically eligible to return in Week 9, but it's more realistic that he'll return around Christmas.