The Bears (4-8) will visit the 49ers (5-7) Sunday in San Francisco. Here are three things that should increase their chances of winning the game:

(1) Establish the run.

A productive rushing attack would help the Bears sustain drives and open up the passing game for rookie quarterback Caleb Williams and his receivers. This season the Bears are 4-2 when rushing for 84 yards or more and 0-6 when they produce fewer than 84 yards. After running for at least 128 yards in four straight games, the Bears have been held under 80 yards in four of their last five contests.

Unfortunately, injuries have impacted their running back room.D'Andre Swift is questionable for Sunday's game with a quad injury that limited him in practice Friday, andRoschon Johnson has been ruled out with a concussion. Swift ranks 19th in the NFL in rushing with 704 yards and five touchdowns on 179 carries. Interim head coach Thomas Brown said Friday that with Johnson inactive against the 49ers, third-string backTravis Homer's role will expand.

San Francisco's defense ranks fifth in the league in total yards and fourth against the pass but just 15th versus the run. The unit is led by linebacker Fred Warner, a three-time first-team All Pro.

"Fred Warner is a problem in more ways than one, with the way he communicates," Brown said. "You try to find different ways to get him looks. If you give him the same presentation, he will diagnose it, communicate with his defense and meet you at the ball. You have to try and figure out how to make some adjustments with that."

Continuing to protect the ball will also be key to the Bears recording a win in Brown's debut as interim head coach. The offense has not committed a turnover in its last five games. The 49ers generated 15 takeaways in their first eight games but have produced only one in their last four contests.

San Francisco is expected to play without defensive end Nick Bosa for the third straight game. The four-time Pro Bowler is listed as doubtful with hip and oblique injuries.

(2) Make San Francisco's offense one-dimensional.

Containing the 49ers running game and putting them in predictable passing situations would allow the Bears defense to crank up its pass rush and potentially create some impact plays. San Francisco's rushing attack took two major hits last Sunday night when running backs Christian McCaffrey (knee) and Jordan Mason (ankle) both sustained season-ending injuries in a loss to the Bills in Buffalo.

The only running back who remains on San Francisco's active roster with at least 10 carries this year is rookie fourth-round pick Isaac Guerendo, who has rushed for 246 yards and two TDs on 42 attempts. In the only two games in which he has had double-digit carries, Guerendo ran for 85 yards on 14 attempts against the Cowboys and 99 yards on 10 carries versus the Seahawks.

Bears defensive coordinator Eric Washington said that the 49ers are "really intent on running the football when they are at their best. They're averaging 30 rushing attempt per game. They complement that with the play-action boot."

It wouldn't be a surprise if the 49ers got receiver Deebo Samuel more involved in the running game. A dual threat in his six seasons with San Francisco, Samuel had 26 rushes in the first nine games this year but has just one in the last three contests.

"He can align at multiple positions," Washington said. "He can play tailback. He can play slot receiver. He can be a wide receiver. He is the key to everything that they desire to do. He's a very versatile player, strong possession guy, can also get behind you, a runner once he possesses the football. We have to be aware of that and make sure that we understand how they're utilizing him and that we do a good job of managing his personnel packages."

Quarterback Brock Purdy ranks 19th in the NFL with a 94.8 passer rating after leading the league with a 113.0 rating last year when the 49ers reached the Super Bowl. Purdy has passed for 2,707 yards with 13 touchdowns and eight interceptions. His top targets are tight end George Kittle (50 receptions for 649 yards and 8 TDs) and receiver Jajuan Jennings (50-684-4).

The 49ers rank seventh in the NFL in total yards, seventh in rushing and ninth in passing. The unit is second in the league in average yards on first down at 6.72.

(3) Get another impressive performance from Caleb Williams.

The rookie quarterback has flourished in the last three games with Brown calling plays, registering passer ratings of 97.8, 103.1 and 95.0 against the Packers, Vikings, and Lions, respectively, three teams that entered Week 14 with a combined record of 30-6. Williams put the Bears in position to win all three of those games by engineering late drives.

The No. 1 overall pick in this year's draft has not thrown an interception in his last six starts, tied for the longest streak by an NFL rookie since at least 1950. His 232 consecutive pass attempts without an interception is the longest streak both in Bears history and by an NFL rookie. Williams has thrown at least 30 passes in the last five games without a pick, the longest such streak since Tom Brady's eight games in 2022 when he was with the Buccaneers.

While preparing for Sunday's contest, 49ers coach Kyle Shanahan described Williams as "as talented as there is."

"The stuff that you saw in college, you can see in the NFL," Shanahan said. "As good of a thrower as there is, born to play the position, got the athletic ability to do whatever, he's got the speed to do whatever. He's gotten a lot of playing time. He's getting better as this year goes. I think he's getting a lot more consistent. I think he's been playing his best ball, probably, here the last few weeks."

Receiver DJ Moore, who is questionable for Sunday's game with a quad injury, leads the Bears and ranks 14th in the NFL with 62 receptions for 663 yards and five touchdowns. Fellow receiver Keenan Allen is coming off his two most productive outings of the year, with nine catches for 86 yards and one TD against the Packers and five receptions for 73 yards and 2 TDs versus the Lions.