The Packers (8-5) play at New England (11-2) Sunday.
Rodgers suffered his second concussion of the season in Green Bay's loss to Detroit last Sunday. He did not practice Wednesday and will likely not take the field the rest of the week. He also was diagnosed with a concussion after a Week 5 loss to Washington.
McCarthy said Rodgers will be evaluated Saturday by the team's medical staff, which will rule on whether or not he is medically fit to play. The coach said he will then decide on Rodger's playing status.
Matt Flynn is Rodgers' backup.