ALLEN PARK — On the final day of preparation before flying to San Francisco on Saturday, four Lions did not practice.

Sitting out were Corey Williams (knee), Louis Delmas (knee), Travis Lewis (quad) and Bill Bentley (concussion).

Lawrence Jackson, who missed Wednesday and Thursday practices, was back at work during the portion of practice open to the media on Friday.

The injury report at 4 p.m. today could list early inactives. It seems pretty clear that Bentley and Delmas will not play. Bentley hasn’t been cleared for contact since sustaining a concussion in the win over the Rams. Delmas hasn’t practiced since knee surgery on Aug. 7.

Expect Chris Houston and Jacob Lacey to start at corner with Drayton Florence at the nickel.

At safety Erik Coleman and John Wendling started last week and should get the nod again.

Kickoff is Sunday at 8:20 p.m. in NBC’s Sunday night game with Al Michaels and Cris Collinsworth calling the game and Michele Tafoya reporting from the sideline.

(Follow @PaulaPasche on Twitter. Order her new book, “100 Things Lions Fans Should Know & Do Before They Die’’ here. It’s also available at bookstores.)