Aaron Rodgers stood helplessly on the sideline in green warmups, hands jammed inside his pockets.

The Packers lost more than just sole possession of first place in the NFC North after falling 27-20 Monday night to the Chicago Bears.

An injury to Rodgers' left (non-throwing) shoulder knocked perhaps the most irreplaceable player in the NFL out in the game's first series, and porous fourth-quarter defense finished off Green Bay's comeback chances against their fierce divisional rivals.

Coach Mike McCarthy said more tests were needed on Rodgers, and that he hoped to know more on Tuesday.

"No timeline, no exact diagnosis," McCarthy said. "That's where we're at."

And they may be in big trouble, too, if the 2011 NFL MVP is out for any significant length of time. Rodgers was hurt after getting pulled down from behind by Shea McClellin, one of three sacks on the night for the defensive end.

Backup Seneca Wallace was 11 of 19 for 114 yards and an interception. Rodgers was 1 of 2 for 27 yards before departing. Starter and backup played toss for a couple minutes, but Rodgers soon afterward was headed off the field for tests.

"I knew he was in a little bit of pain, but didn't know what was going on," Wallace said.

Wallace hadn't played in a game since Jan. 1, 2012, when he was with the Browns — a 13-9 loss to the Steelers.

On Monday night at least, the Bears had a better insurance policy at quarterback.

Josh McCown, playing in place of the injured Jay Cutler, threw for two touchdowns to help the Bears end a six-game skid to Green Bay. The loss snapped Green Bay's four-game winning streak, and forged a three-way tie at 5-3 atop the division between the Packers, Bears and Detroit Lions, who had a bye this week.

Bears return specialist Devin Hester likened the Packers without Rodgers to the X-Men without one of their most valuable members.

"Fighting the X-Man and the Wolverine goes down," Hester said. "He's like the bread-and-butter of their team."

Alshon Jeffery had five catches for 60 yards, including a 6-yard grab for the go-ahead touchdown at the end of the third quarter. Brandon Marshall, largely shut down in two games against Green Bay last year, had seven catches for 107 yards and a score. Matt Forte ran for 125 yards and a TD, and also had 54 yards receiving.

"We have a long road ahead. It doesn't mean much right now," Trestman said about the first-place tie. "It will mean a lot more down the road here."

The loss spoiled another big night by Green Bay rookie Eddie Lacy, who ran for 150 yards and a touchdown on 22 carries. The rejuvenated running game also featured a 32-yard touchdown run from James Starks in the first quarter.

All of it overshadowed by Rodgers' injury, the latest in a season filled with bad health news for Green Bay.

James Jones (knee) returned Monday night after a two-game absence, but sackmaster Clay Matthews (thumb) and tight end Jermichael Finley (neck) are still out. Wide receiver Randall Cobb (leg) is also on the injured list-designated to return, and offensive lineman T.J. Lang (concussion) and linebacker Andy Mulumba (ankle) were also banged up during the game.

But a hurt Aaron Rodgers is Green Bay's ultimate nightmare. He hasn't missed a game due to injury since Dec. 19, 2010.

"Aaron's a huge part of our offense," McCarthy said. "This is a thing that's been built over time with Aaron as the centerpiece. I don't think it's realistic to put anyone in there and expect him to perform" like Rodgers.

Rodgers, though, doesn't play defense, and Green Bay played poorly on that side of the ball in the fourth quarter.

The Bears locked the game up with an 18-play, 80-yard drive in the fourth quarter that started with 9:48 left and ended with a 27-yard field goal by Robbie Gould for a seven-point lead with 53 seconds left. Chicago converted on a fourth-and-1 at its own 32 with a 4-yard run by Forte, and added two third-down conversions later in the drive.

"Frustrating, man, really frustrating," Packers defensive lineman B.J. Raji said. "That's not like us. But give the Bears credit."


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