GREEN BAY, Wis. (AP) - It looked harmless enough - quarterback Aaron Rodgers and backup Seneca Wallace playing a light game of toss on the sideline with the Packers on defense in the first quarter.
They were the last throws Rodgers would make Monday night in the 27-20 loss to the Chicago Bears.
''I knew he was a in a little bit of pain, but no, we didn't know what was going on,'' Wallace said.
Next thing Wallace knew, he was takings snaps behind center and Rodgers was headed into the locker room for tests. The nightmare scenario for every Packers fan had come to fruition.
Rodgers emerged in the third quarter wearing a Packers cap and green warmups after being diagnosed with an injured left (non-throwing) shoulder following a sack on the first series by Shea McLellin.
''We never want to see anybody get hurt, and he's one of the great, great players in our game,'' Bears coach Marc Trestman said. ''Certainly nobody wants to see him get hurt.''
Oh yeah, the Bears won, with their own backup quarterback, no less.
Josh McCown, playing in place of the injured Jay Cutler, threw two touchdown passes in a victory that ended a six-game skid to its NFC North rivals and forced a three-way tie atop the division with the Lions, who were idle this week. All three teams are 5-3.
Here's more on Rodgers' injury - and four other things learned in Monday night's roller-coaster of a game.
OH, AARON: Coach Mike McCarthy hoped to have more information on the health of his star quarterback on Tuesday following more tests. Rodgers hasn't missed a game due to injury since Dec. 19, 2010.
The 2011 NFL MVP looked stoic on the sideline while trainers checked on his upper body after the sack. He later had his hands jammed into his pockets when he returned to the sideline, briefly letting out the right arm for some moments to wave to the crowd.
''He has a shoulder injury,'' Packers coach Mike McCarthy said. ''They want to run more tests. They don't have an exact diagnosis. We'll have more information, probably tomorrow.''
Pressed for more information, McCarthy insisted there wasn't any.
''No timeline, no exact diagnosis,'' he said. ''That's where we're at.''
BETTER BACKUP: Wallace was 11 for 19 for 114 yards and an interception. The Bears had their own quarterback issues with Cutler out with a groin injury.
McCown turned out to be more than a suitable replacement. He finished 22 of 41 for 272 yards and two touchdowns.
The 11th-year veteran from Sam Houston State will remember this game for a while.
''It would be hard to find one better than this,'' he said. ''This is really neat because it means so much to our team ... and is for the divisional lead.''
PULLING AWAY: The Bears locked the game up 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.
Trestman didn't rely on statistics in making the gutsy call. ''It was a sense that we needed to stay on the field and I felt that we could,'' he said.
ON THE RUN: The Packers lost their starting quarterback but got a breakout game from rookie running back Eddie Lacy.
The 5-foot-11 Lacy bulldozed his way to 150 yards on 22 carries, including a career-best 56-yarder that set up his 1-yard touchdown run that tied the game at 17 in the third quarter.
He was a handful all game long, like on a 12-yard run up the left sideline that ended with Bears safety Major Wright spinning to the ground. Lacy pounded his chest with his right hand and yelled nearby, as if proclaiming his arrival in the Monday night spotlight.
WHO'S NEXT: Calling Matt Flynn?
Jettisoned this season by Oakland and Buffalo, Flynn has had success in Green Bay as Rodgers' backup. Flynn set the franchise record for passing yards in a game with 480 on Jan. 1, 2012 against the Lions, starting when a healthy Rodgers rested for the playoffs. Rodgers tied that record in September in a win over the Redskins.
McCarthy's focus was trained on his current roster.
''Player acquisition, I really have nothing for you,'' he said. ''I'm focused on Seneca Wallace right now.''
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