GREEN BAY, Wis. (AP) -- Quarterback Aaron Rodgers left Monday night's game with an injury to his non-throwing shoulder before Bears backup Josh McCown threw two touchdown passes to give Chicago a 24-20 lead over the Green Bay Packers after three quarters.
Rodgers hurt his left shoulder when he was sacked while scrambling to his right on a third-and-8 at the Bears 12 by defensive end Shea McClellin with 12:38 to go in the first quarter.
A trainer looked at Rodgers' upper body on the bench. The 2011 NFL MVP took a few tosses on the sideline, then was attended to again before running inside Lambeau Stadium for tests. He was ruled out early in the second quarter. But he returned to the sideline in green Packers warmup gear, drawing cheers while giving a thumbs-up sign with his right hand while keeping his left hand in his pocket.
Rodgers hasn't missed a game because of injury since Dec. 19, 2010, when he had a concussion.
A worst-case scenario for the Packers came to fruition: backup Seneca Wallace had to take over at quarterback. Rodgers' injury turned this high-profile matchup with the Bears into the Battle of the Backups. McCown started for Jay Cutler, who was out with a groin injury.
And the Bears didn't back down after giving McCown two weeks to prepare following a bye. He fared well in the first half, benefiting from Bears receivers gaining chunks of yards after catches.
It helped having a pair of tall receivers to throw to in 6-foot-4 Brandon Marshall and 6-3 Alshon Jeffery. McCown and Jeffery connected for a 6-yard touchdown pass with 2:46 in the third to give the Bears its four-point lead in a topsy-turvy game.
McCown was 19 of 33 for 244 yards after three quarters. He also scrambled 20 yards to the Packers 6 on third-and-9 to save a late drive that ended with Gould's 24-yard field goal with time expiring in the first half.
Marshall had six catches for 96 yards and a touchdown catch for Chicago.
With Rodgers out, coach Mike McCarthy relied on special teams and a rejuvenated rushing attack to keep up.
Rookie Eddie Lacy had 142 yards rushing on 18 carries and a career-long 56-yard run after bursting up the middle on the team's first play from scrimmage in the second half. He scored from 1 yard on the next play to make it 17-all.
McCarthy then elected to go with an onside kick that was recovered by the Packers' Jamari Lattimore at the their own 49. On the next play, Lacy barreled down the left sideline for a 12-yard run that ended with Bears safety Major Wright spun down to the ground. Nearby, Lacy pounded his chest with his right arm.
That drive ended with a 23-yard field goal by Mason Crosby, the second of two good kicks on the night.
James Starks darted up the middle for a touchdown with 3:45 in the first quarter to give Green Bay a 10-7 lead, one play after a lunging Lattimore blocked a punt by Chicago's Adam Podlesh that was recovered by Chris Banjo at the Bears 32.
Starks six carries for 40 yards going into the fourth quarter.
Wallace had a short pass tipped in the first half by Julius Peppers, who then jumped and tipped the ball again, as if going for a rebound, before gaining control for an interception and returning it 14 yards to Packers 45.
The Bears' momentum was erased four plays later by the blocked punt and Starks' touchdown run.
McCown connected with Marshall for a 23-yard touchdown pass and a 7-3 lead on the possession after Rodgers got hurt. The Packers settled for a 30-yard field goal on that drive.
Wallace hadn't played in a game since Jan. 1, 2012, when he was with the Browns - a 13-9 loss to the Steelers.
Until Rodgers' departure, the Packers got good news on the injury front. Receiver James Jones was active Monday after missing two games with a knee injury, and linebacker Brad Jones returned after missing three games with a sore hamstring.
But Right guard T.J. Lang left the game with a concussion.
The offense is already out receiver Randall Cobb (leg) and tight end Jermichael Finley (neck), while the defense is minus pass-rushing linebacker Clay Matthews.
Chicago was also as hamstrung, playing without linebacker Lance Briggs (shoulder).
It was the 187th meeting of the league's oldest rivalry, which dates back to 1921.
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