The trouble is, that hasn't stopped the questions about which one of them is better suited to lead the Monsters of the Midway as they make a run for Super Bowl XLI.
"I thought I was going to play the whole game," Grossman said afterward in the locker room. "But I guess they had plans that they were going to get me out mid-third quarter."
Griese directed a 72-yard drive that put Pro Bowl kicker Robbie Gould in position for a go-ahead field goal midway through the fourth quarter and completed a pass to set up Gould's fourth field goal, giving Chicago a five-point cushion with 2:50 left.
"I hadn't played in a while, so it felt good to get out there and contribute to a win," said Griese, who didn't play in the previous seven games after being used sparingly in reserve duty. "I'm ready to play whenever they want me to, but I don't have any expectations."
Switching QBs added a touch of intrigue to a game with nothing at stake.
The Bears (13-2) clinched home-field advantage throughout the NFC playoffs last week, and Detroit (2-13) has been relegated to playing for pride since midseason - for the sixth straight year.
One possession after Jon Kitna's NFL-high 30th turnover, the Lions had a shot to win but came up short as they have often this season.
Kitna threw a pass into the end zone on the final play that leaping wide receiver Mike Williams got his hands on but couldn't control in the end zone while being closely defended by cornerback Devin Hester. Williams, a highly-disappointing 2005 first-round draft pick, dropped several passes on the day.
"I owe it to myself and the team to make that play," Williams said. "That's just a play you make."
Smith insisted before the game that he would play to win and not to avoid injuries by using his starters as long as necessary in the hopes of staying sharp for the playoffs.
After the game, Smith said the move at QB was planned all along.
"We wanted to get a win in the worst way, and we wanted to look at a few other players," Smith said.
Smith stuck with Grossman earlier this month as his starting QB despite committing 18 turnovers in a seven-game stretch.
Grossman responded by throwing four TDs without an interception in the next two games, adding a career-high 339 yards passing last week, in two wins that helped Chicago earn the right to play in the Windy City throughout the NFC playoffs.
Against the Lions, he had another up-and-down performance in what has been an up-and-down season. Chicago still won its fourth straight.
Grossman was 20-of-36 for 197 yards with a TD. Griese was 6-of-9 for 51 yards.
Bernard Berrian's 13-yard score early in the second quarter gave the Bears the lead and was one of the only highlights Grossman had in a game that could lead to speculation during the final week of the regular season and into the playoffs.
"We'll leave the decisions up to the coaching staff," said wide receiver Muhsin Muhammad, whom Grossman overthrew badly on a double-move that likely would've been a touchdown in the third quarter. "I'm confident with both guys, but Rex has been our guy all season."
But Kitna fumbled when super rookie Mark Anderson sacked him late in the game, adding to his long line of miscues at crucial times. Adewale Ogunleye's recovery at the Detroit 32 with 3:46 left set up a field goal that forced the Lions to go for a TD on their final drive.
"We turned the ball over one time, but that was one time too many," Detroit head coach Rod Marinelli said. "We didn't get any on defense, and that's critical in a game like this."
Like many games this season, the Lions were solid at times and had a shot to win but made too many mistakes.
"That's just how our year has gone," Campbell said.
Detroit has lost seven straight and is an NFL-worst 23-72 since 2001 under the direction of general manager Matt Millen.
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