Polamalu practiced Friday with the Steelers' starters and is planning to play Sunday against the unbeaten Vikings. He did not practice Wednesday or Thursday.
The five-time Pro Bowl safety tore the medial collateral ligament in his left knee Sept. 10 against Tennessee.
He returned last Sunday to make an interception against Cleveland, although he said an additional week or two off would have helped the knee recover faster.
After practicing Friday with a knee brace, Polamalu plans to try to wear it Sunday. He discarded the brace after going through pregame warmups before the Cleveland game, saying it restricted his running.