Dorsey was carted off the field with a knee injury on Sunday and did not return to the game. Head coach Jim Tomsula said after the game that the team was fearful Dorsey had torn his ACL.
Dorsey, 30, has one year remaining on the contract extension he signed in 2014.
Arik Armstead, a rookie first-round pick, replaced Dorsey when he went out on Sunday.
Dorsey has played in all 10 of San Francisco’s games thus far and made seven starts. He missed all of last season with a torn biceps.
- Dan Gartland