|Brett Favre flips the ball forward to avoid a sack against the Panthers.(AP)|
Rivera sprained his medial collateral ligament and will have an MRI on Sunday, coach Mike Sherman said.
"When Brett's standing over him and telling him to get up and he doesn't move, you think, 'Oh, man," center Mike Flanagan said.
Sherman said it might not be as bad as first feared.
"When I talked to the doctors, there is a chance he could be ready for the (opener), believe it or not," Sherman said. "But there's a chance he won't be, either."
As for Brown, Sherman gave him a passing grade after the super-sized nose tackle helped stuff Stephen Davis four times on a goal-line stand in his first test to see if he'll be able to play with a ruptured right biceps.
"It certainly seemed like he did his job from my vantage point on the sideline," Sherman said.
Brown, who played one quarter, wasn't going to jump to conclusions.
"It's still a little sore," he said. "But we all expected that. We'll see how it feels tomorrow."
Carolina (3-0) got outstanding performances from backup Chris Weinke and Walter Young, who hooked up five times for 88 yards, including an 11-yard go-ahead touchdown on the first play of the fourth quarter.
Weinke was 8-of-10 passes for 107 yards.
The Packers (2-2) also lost safety Darren Sharper (groin), but he said it wasn't serious. Carolina's most serious injuries were to defensive end Michael Rucker (sprained left ankle) and free safety Deon Grant (left quadriceps strain).
Brown wants to play through his injury rather than undergo season-ending surgery even though he's risking permanent loss of strength in the arm.
Brown, a 10-year veteran and fan favorite, got a rousing ovation from the record crowd of 69,831 at the renovated Lambeau Field when he dumped Davis for a 1-yard loss on Carolina's first possession, then did his trademark "gravedigger" celebration.
Brown didn't take a cortisone shot or wear a brace because he wanted to be able to fully test the muscle, which he ruptured on a freak play two weeks ago at Atlanta.
"Man, he was out there fighting," Sharper said. "To play with a torn biceps shows the true heart and guts that he has. He's playing with one arm and still fighting through double teams. That was tremendous."
Ahman Green rushed 12 times for 77 yards, his last carry a 45-yard scamper for a touchdown that put Green Bay ahead 7-3 in the third quarter.
"That was good to see," Favre said. "But I would have liked to see things click a bit better."
Henderson also fumbled away the ball on the Packers' first play from scrimmage. Favre threw two interceptions and Green Bay's seven first-half possessions ended in four punts and three turnovers.
Carolina's starters didn't fair much better. After Davis failed to punch the ball in from the 1, the Panthers had four punts and an interception by Rodney Peete the rest of the half.
"It's always easier for the defense," Carolina cornerback Terry Cousin said. "Everything we do is read, react, attack. Offense, it takes some time for the guys to jell."
Panthers coach John Fox blamed himself for Davis's failure to score the ball in from the 1.
"We could have kicked a field goal there, so we came away with nothing," Fox said. "I was disappointed we weren't able to punch it in from the half-yard line."
After Favre guided Green Bay on its lone scoring drive, backups Doug Pederson and Craig Nall didn't complete a pass and Akili Smith was 3-for-12 for 20 yards and threw an interception in the closing minute that William Hampton returned 30 yards for a TD.
"Our second-half offense was terrible," Sherman said. "They couldn't crack an egg out there."
|FG||John Kasay 26 Yd, 13:48. Drive: 4 plays, 26 yards in 1:12.|
|FG||Shayne Graham 42 Yd, 6:38. Drive: 10 plays, 51 yards in 4:23.|
|TD||Walter Young, 11 Yd pass from Chris Weinke (John Kasay kick is good), 14:56. Drive: 10 plays, 65 yards in 5:20.|
|TD||William Hampton, 30 Yd interception return (Shayne Graham kick is good), 0:56.|
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