CHICAGO (AP) - Jay Cutler insisted his groin was OK. It was the left ankle injury that really bothered him.
Cutler was pulled before Chicago's final drive and the Bears' rally ended when Matt Forte was dragged down in the backfield on a pivotal 2-point conversion attempt, sending the Detroit Lions to a 21-19 victory on Sunday in a key matchup of NFC North rivals.
''We didn't execute offensively the way we needed to execute, particularly in the running game,'' Bears coach Marc Trestman said. ''We just didn't get it done.''
Cutler threw for 250 yards and a touchdown in his first action since he injured his groin last month. He hurt his ankle in the second quarter and looked progressively worse as the game wore on.
Trestman finally decided to put in Josh McCown when the Bears (5-4) got the ball back with 2:17 left.
''I just felt really restricted in the pocket in what I was able to do and it wasn't getting out as quick and some of the throws didn't have as much on them as I wanted,'' Cutler said. ''And I knew Josh was ready to go and I just didn't want to get to a point where I was hurting us more than I was helping us.''
Cutler said he isn't sure if he will be able to play next Sunday against Baltimore.
McCown drove the Bears down the field, throwing an 11-yard touchdown pass to Brandon Marshall with 40 seconds left. After a roughing penalty on Willie Young gave the Bears another chance at the tying 2-point conversion, Nick Fairley threw Forte down to preserve the win for Detroit.
''I just figured it would be a run or a play-action pass,'' Fairley said. ''I just scouted out the ball real good and it was just happy I made the play.''
Calvin Johnson had two second-half touchdown receptions and Reggie Bush rushed for 105 yards as Detroit (6-3) swept the season series against Chicago for the first time since the 2007 season. The Lions lead the Bears and Packers by a game in the division.
''We came out with a victory on the road against a really tough team,'' coach Jim Schwartz said. ''It was a hard-fought win. Proud of the players, but that's the only thing that means (anything) today.
''I mean first place, you don't get any prizes for first place there nine games into the season.''
Johnson's touchdown grab with 2:22 left was the 63rd of his career, breaking a tie with Herman Moore for Detroit's franchise record. Moore still leads with 670 career receptions for the Lions, but Johnson might take that record down at some point, too.
''To be a part of history for the Lions, that's a big deal,'' Johnson said.
The Lions were clinging to a 14-10 lead when Chris Conte intercepted an overthrown ball by Matthew Stafford and returned it 35 yards to the Detroit 9.
Forte then had a touchdown run negated by a holding penalty on left guard Matt Slauson and an apparent scoring pass to Alshon Jeffery was overturned when a replay showed he lost control of the ball when he hit the ground.
Robbie Gould's 32-yard field goal trimmed the Lions' lead to one with 9:17 remaining, setting the stage for the frantic finish.
''For the offense and really for our team it was really a day of missed opportunities,'' Trestman said.
It was Cutler's first game since he was sacked by Redskins nose tackle Chris Baker in the first half of Chicago's 45-41 loss at Washington on Oct. 20. He had to be helped off the field, and an MRI revealed a torn groin muscle that was expected to sideline the quarterback for at least four weeks.
Cutler had other ideas.
The Bears had a bye week after the Washington loss, and Cutler watched while McCown led Chicago to a big 27-20 victory at Green Bay last Monday. Cutler then was cleared to play on Thursday and made the start against Detroit with the Lions, Bears and Packers all tied for the NFC North lead entering Sunday.
He insisted he was 100 percent, but it was clear his groin was bothering him more and more as the game wore on. He grabbed his groin area and dropped to the ground after one third-quarter throw. He then popped right back up and remained in the game.
''It held up OK. It's all on the same leg so I think that was a problem,'' said Cutler, referring the groin and ankle injuries. ''But the groin, you take the ankle out of the equation and I would have been fine, I think.
Cutler threw a 32-yard touchdown pass to Marshall on the first drive of the game. But he also had a pass tipped by Ndamukong Suh and grabbed by DeAndre Levy in the end zone for the linebacker's fifth interception.
NOTES: Levy began the day tied with seven other players for the NFL lead in interceptions. ... Each team played without a key defensive end. Detroit rookie Ziggy Ansah was out with a left ankle injury, and Chicago's Shea McClellin tweaked a hamstring during practice after he had three sacks in the victory at Green Bay. ... Lions RB Montell Owens left in the first quarter with a knee injury and did not return.
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