With Matthew Stafford (shoulder) and Shaun Hill (finger) both out, the Lions are forced to start third-string QB Drew Stanton, who may be a better runner than passer. The Lions are the sixth team this season to have used at least three different starting quarterbacks. Against the Dolphins on Nov. 18, the Bears harassed third-stringer Tyler Thigpen with six sacks, including three by Julius Peppers. That will be the plan again this week, but first the Bears will want to eliminate the Lions’ struggling run game with Maurice Morris taking over for banged-up Jahvid Best. The Chicago defense has played well much of the season, but has really been lights-out lately on third down. The Bears have allowed only six conversions in 33 third-down attempts in the past three games.