Now, they will try to secure their first division title in more than two decades.
''It's what you play the game for,'' Stafford said. ''You play the game to play extremely meaningful games in December. They'll be excited for it. I know everybody in our locker room will be excited as well.''
None will be more meaningful than next week's game at Green Bay, where the Lions haven't won since 1991 and the NFC North will be decided.
Chicago (5-10) benched Cutler days earlier, having seen enough after he led the NFL with 18 interceptions and 24 turnovers in the first year of a seven-year contract he signed in the offseason. They turned to the cast-off Clausen, who hadn't started a game since 2010.
Stafford outplayed Clausen, but just barely. He completed 22 of 39 passes for 243 yards and hit the 4,000-yard mark for the fourth straight year, but it was hardly an easy afternoon for him.
''We stood tall,'' Bears coach Marc Trestman said. ''We played hard. We're not trying to sugar-coat it. We didn't win. We're here to win. But I felt our players were in it to win for four quarters today but I've felt that way throughout the season. That hasn't changed.''
Ndamukong Suh had two sacks, and Calvin Johnson caught six passes for 103 yards. The Lions (11-4) make their second trip to the postseason in four years and third in 16 years after Philadelphia's loss to Washington on Saturday.
They were hoping to lock up their first division championship since 1993. But with the Packers beating Tampa Bay, the North will be decided in next week's game.
Here are some things we learned from this game:
OVERCOMING ERRORS: It was far from a perfect performance by the Lions.
Stafford threw interceptions in the end zone and near the goal line on back-to-back possessions in the second quarter with the Lions leading 7-0.
Jeremy Ross muffed a punt near the end of the first half, leading to a touchdown for Chicago, and center Dominic Raiola stepped on Chicago defensive tackle Ego Ferguson's right ankle while he was on the ground early in the third quarter.
Despite all that, the Lions came away with their highest win total since they went 12-4 in 1991.
GAINING GROUND: The Lions might be getting their running game in order. They finished with a season-high 138 yards rushing, the fourth time they've hit the 100-yard mark this season.
Reggie Bush, who's been injured at times, ran for a touchdown and 54 yards. He added 44 yards receiving, and Detroit handed Chicago its fourth straight loss.
CLAUSEN OR CUTLER?: The big question this week for the Bears will be one they never envisioned having to answer as long as Cutler was healthy. Who will start at quarterback? Will it be Clausen again?
He completed 23 of 39 passes for 181 yards in his first start since his 2010 rookie season with Carolina. He threw touchdowns to Matt Forte and Alshon Jeffery and played turnover-free ball until a late interception by Glover Quin.
YOUNG PLAYERS STEP UP: Even though Johnson had more than 100 yards, this was big improvement for Bears cornerback Kyle Fuller over their meeting on Thanksgiving. Johnson had 11 catches for 146 yards in that game to lead the Lions to an easy win.
Rookie Brock Vereen also had his first career interception for Chicago when he picked off Stafford in the end zone in the second quarter.
THE COLD NUMBERS: The Lions cleared one obstacle on Sunday - they won in the cold. The game-time temperature was 36, but the Lions came away with the win after dropping 18 straight including the playoffs when it was below 40.
The last time they did that? Dec. 26, 1993, at Chicago.
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