Bears RB Jeremy Langford will fill in for injured starter Matt Forte this week. Dennis Wierzbicki USA TODAY Sports

If the Chicago Bears want to escape San Diego with a win, a few players must step up with game-changing contributions against the Chargers on Monday night. A couple key reserves will be asked to help carry the load on offense, while the defense tries to find a way to slow down Chargers quarterback Philip Rivers and his passing attack.

Here are three Bears who must respond to the call in Week 9:

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Jeremy Langford, running back

Chicago's do-it-all running back, Matt Forte, is out with a knee injury, so it's time for Jeremy Langford to make his debut at running back. Langford, a fourth-round pick out of Michigan State in this year's draft, has not seen a ton of playing time while backing up Forte. The rookie has only carried the ball 27 times for 80 yards through his first seven games, but he already has two NFL touchdowns under his belt. In order to fill Forte's role, Langford will need to really step up as a receiving target out of the backfield. He has caught just two passes as a professional.

Marquess Wilson, wide receiver

The Bears will also be without wide receiver Eddie Royal on Monday night, so Marquess Wilson needs to experience a bit of a resurgence in his place. Wilson has developed into a decent deep threat this season, as his average of 16.8 yards per catch is the highest on the team (min. 10 catches). What the Bears need to do is target him more often, since he only has 18 receptions on the season. If Wilson makes the Chargers respect him as a secondary target, No. 1 wideout Alshon Jeffery should benefit from the coverage adjustments that are bound to happen.

Adrian Amos, safety

Chicago's secondary hasn't been great this season, but Adrian Amos is a definite bright spot at safety. Amos, a fifth-round selection in this year's draft, rose up the ranks to claim a starting job and has since overtaken second-year cornerback Kyle Fuller as the most promising young member of the Bears' defensive backfield. Rivers averages more than 40 pass attempts per game, so the rookie safety should get plenty of opportunities to have his name called on one of the game's biggest stages.

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