LAKE FOREST—When the Bears take on the 49ers Monday night, they’ll be without quarterback Jay Cutler, the team announced on Friday. Jason Campbell will start in his place.Cutler, who suffered a concussion against the Texans last Sunday night, left the game at halftime was replaced by Campbell for the remainder of the game.The starting quarterback’s been limited this week in terms of practice and hasn’t been available to the media either, leading to the (eventually correct) speculation that Cutler wouldn’t play against San Francisco.Campbell now has a large task in front of him, although he certainly sounded prepared on Friday when he took to Twitter.Monday night’s game is an interesting litmus test for the Bears backup. He struggled against the Texans, but the weather was awful, he didn’t prepare to start and first one to 10 was winning that game.The Bears signed Campbell this offseason in a direct response to the disaster that was Caleb Hanie down the stretch in 2011. They were in prime position to make the playoffs and Hanie couldn’t produce a modicum of offense against the easiest of opponents, leading to a Bears freefall out of the postseason.Campbell simply needs to perform adequately enough to let the defense and running game take over against San Francisco and how many more games Cutler misses. If he can guide the Bears to a win on Monday night, fans and members of the organization can breathe a big sigh of relief.