Quinn knows how Terry Shea's offense works, having practiced it in Kansas City the past two seasons. The question is whether he can run it.
"We have to move on and win games with Jon Quinn," tight end Dustin Lyman said. "We're lucky that we have Jon Quinn. He's a good quarterback, he knows this offense really well, and I think everyone will feel comfortable catching the ball from him. It's just too bad that we're going to be without Rex."
For the most part the offense had avoided the crippling injuries that have beset the Bears' defense, but the loss of Grossman comes at an unfortunate time since he was playing the best football of his pro career. Grossman guided the Bears to 392 yards of total offense before he was hurt, completing 9 of his last 10 passes for 102 yards.
But now it's up to Quinn, who has thrown a total of 128 passes in his seven-year career. His lack of experience may pale in comparison to the concern over the 6-foot-6, 240-pounder's propensity for getting sacked. He's been dropped 16 times in limited duty, and compared to Grossman, Quinn is methodical in his drops, reads and release.
But offensive tackle John Tait, who spent two seasons with Quinn in Kansas City, said the veteran has enough experience and knowledge of the system to succeed.
"He's a great quarterback," Tait said. "I think he's the best-case scenario for us as far as somebody going down. Jon is very comfortable coming in."
But he might not be so comfortable on Sunday against the Eagles, who had four sacks in Week Three, including three by Jevon Kearse.