That's why the Bears believe they can get by without Cutler, at least for now. They have an experienced backup and don't expect the same sort of meltdown.
"I understand a year ago what happened, but at the same time, I've got to do what I've got to do within the system, different football team," Campbell said.
The Bears lead the NFC North at 7-2, one of the top records in the NFC. But they are in the tightest division in the league, with Green Bay at 6-3, the Vikings at 6-4 and Detroit still in the picture at 4-5.
Campbell, who threw for 94 yards last week, started six games for Oakland a year ago before breaking his collarbone. He has completed more than 60 percent of his attempts and thrown for 14,511 yards since he entered the league in 2005.
"I think both of them have ability to make any throw on the field," said 49ers cornerback Carlos Rogers, Campbell's friend and teammate in Washington.
Marshall said Cutler is more mobile and Campbell a bit more comfortable in the pocket.
"It's the opposite, you would think Campbell would be like Vick," he said. "But Jay Cut is like (Michael) Vick, and Jason is more of a pocket guy, I would say. Cut likes to run around a little bit, so that's a little opposite. But because of the picture we paint on black quarterbacks, it's supposed to be a guy who runs around a lot, but Jason does a good job in the pocket, really reading coverage, really taking control of the offense. We're fortunate to have him."
Until this week, Campbell really hadn't worked with the starters in practice since training camp.
How fast he can get on the same page with the rest of the starters remains to be seen, even if the players don't expect any problems there.
In particular, it'll be interesting to see how the dynamic between the star receiver and the quarterback changes. Cutler has a long history with Marshall from their days in Denver and has been leaning on him.
"I can't make up for four years that they've been together," Campbell said. "But at the same time, you can see that on the field, when they play together, they see certain things together. A lot of that comes from the experience that they have from back in their days in Denver. But for me, just talking to B, we'll pretty much do what we do. At the same time, if we see things, then we see things. But we're not going to be trying to push the envelope on things that are just not there."
Notes: LB Brian Urlacher (coach's decision) and DT Matt Toeaina (calf) did not practice.
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