Coming off their worst loss in more than five years, the Chicago Bears will try to take advantage of the limping St. Louis Rams in Sunday's game at the Edward Jones Dome.

Even against a woeful St. Louis team, the Bears (5-5) could struggle to bounce back if they play as they did last Sunday in a 37-3 defeat at Green Bay. Their worst loss since a 49-7 drubbing to San Francisco in the 2003 season opener dropped them into a tie atop the NFC North with Minnesota and Green Bay.

In its second straight loss, Chicago had a season-low 234 total yards and scored its fewest points since last season's opening game, a 14-3 defeat to San Diego.

After missing a game-and-a-half with a sprained right ankle, quarterback Kyle Orton went 13-for-26 for 133 yards and fumbled a snap that was returned for a touchdown. He was replaced midway through the fourth quarter by Rex Grossman.

The 50-percent completion rate was Orton's lowest in a game this season and the 133 yards were his fewest in a full game, but the Bears will stick with him for Sunday.

"We have a lot confidence in him. I think every guy does, we just have to, everybody has to help out," offensive coordinator Ron Turner said. "I'm not worried about his confidence at all. He'll come back and we'll all bounce back from this one."

While Grossman entering for Orton last week was simply because the game was out of reach, Devin Hester getting replaced by Danieal Manning on kick returns in the fourth quarter was a surprising move that could have more relevance.

Hester had two kick returns for TDs in his only game against St. Louis in 2006 and he scored 11 return touchdowns through his first two seasons, but he hasn't reached the end zone this year.

He has averaged 21.8 yards on kick returns to rank 32nd in the league and 6.3 yards on punts to rank 21st after leading the NFC with a 15.5 average last season. Manning led the league in kick return average during the preseason and averaged 27.3 yards on three returns in last week's game -- nearly five more than Hester did on five attempts.

"We'll keep all of our options open," Bears coach Lovie Smith told the team's official Web site. "Danieal came in and gave us a little spark ... We haven't gotten a lot of production from our returns up until this point."

The run defense had been giving Smith exactly what he wanted all season until last Sunday. A week after holding the unbeaten Tennessee Titans to 20 yards rushing, the Bears gave up a season-high 200 -- the most since Minnesota ran for 311 on them on Oct 24, 2007.

Chicago, though, now faces an injury-plagued St. Louis offense that will be missing Pro Bowl tackle Orlando Pace (knee) and top rusher Steven Jackson (thigh). Plus, Rams guard Richie Incognito could be out with a strained rotator cuff.

Losers of four straight, the Rams (2-8) have been blown out in their last three games by a combined 116-32 score while committing 11 turnovers.

Three of those came last Sunday, when St. Louis trailed by 32 points by halftime in a 35-16 loss at San Francisco.

"It has nothing to do with coaches. It's up to us to make plays, and we're not doing it," Rams quarterback Marc Bulger said.

Despite six interceptions to four touchdowns in his last four games while posting a dismal 66.3 quarterback rating, Bulger is keeping the starting job over Trent Green.

"Just talking to all the offensive coaches, they felt that Marc right now still gives us our best chance to win," St. Louis coach Jim Haslett said.

Bulger is 2-1 against the Bears, throwing for 943 yards with seven TDs and four interceptions.

The Rams are last in the league with 317 points allowed and rank 30th in total defense, surrendering 392.1 yards per game.

The Bears ended a four-game losing streak in this series with a 47-27 win in St. Louis in 2006.