Roethlisberger was injured midway through the second quarter of a 30-15 loss Sunday to the Miami Dolphins when he stepped out of a tackle try by defensive tackle Jordan Phillips and hyperextended the knee. His subsequent pass on the play was intercepted by safety Reshad Jones.
Roethlisberger immediately went to the locker room and missed the rest of the first half but returned to play the second half.
The Steelers play the New England Patriots on Sunday at Heinz Field and then have their off week. It is possible he could return to play Nov. 6 against the Baltimore Ravens.
Landry Jones, who replaced Roethlisberger in the second quarter Sunday, is expected to get the start against the Patriots.