GREEN BAY – Dallas receiver Dez Bryant was supposed to be Sam Shields’ responsibility on Sunday.

But when it became rookie cornerback Damarious Randall’s job instead to shadow the Cowboys’ top weapon in the passing game, the Packers’ defense didn’t skip a beat in a 28-7 victory at Lambeau Field.

Bryant had just one catch on three targets for nine yards against Shields early in the game before Shields left with a concussion. From there, Randall shut out Bryant, allowing no catches as only three passes came his way the rest of the game.

“I was just ready, ready for the moment,” said Randall, Green Bay’s first-round draft pick last spring. “I think I had a great week of practice.

“I was just trying to make sure I did my technique, and if I did what I had to do, everything else would take care of itself.”

Shields got hurt midway through the second quarter when he tackled Dallas receiver Lucky Whitehead and tumbled out of bounds on the Cowboys sideline amidst several bystanders. He went straight to the locker room to be evaluated without even coming back to Green Bay’s sideline, and it was determined he had a concussion.

On the very next snap, a third-and-5 in Dallas territory, Cowboys backup QB Matt Cassel went right after Randall on a deep ball to Bryant, who appeared to make the catch for a 28-yard gain. Replays showed the ball slipped from Bryant’s grasp as he fell to the ground, though, and the Packers successfully challenged the call, which was overturned without nearly the level of controversy as Bryant’s non-catch in last January’s playoffs.

“That was kind of funny,” said Randall, who knew all about the Bryant play from watching it on TV 11 months ago. “Once I looked up and saw it, I was like, ‘Oh God, here we go again.’”

It turned out to be a big call, but it was Shields who made the defense’s biggest play of the game before exiting.

On the Cowboys’ first drive, a 50-yard run by Darren McFadden eventually led to a goal-to-go situation, but on third down, Cassel’s slant pass for Bryant deflected off the receiver’s hands, and Shields alertly snagged it for an interception that kept the game scoreless.

“That was critical, to just keep them up out of the end zone and keep them from putting points on the board,” Randall said. “In the NFL, everybody wants to score first.”

The interception was Shields’ third on the season, moving him out of a four-way tie for the team lead. It was also his third career interception against the Cowboys, one in each regular-season game he has played against them.

Sack drought ends: It’s almost hard to believe, but Packers linebacker Clay Matthews had gone seven games without a sack when he finally got one Sunday.

With the Packers protecting a 14-7 lead, Matthews sacked Cassel on the first play of the fourth quarter, coming unblocked on a delayed blitz on third down and laying a big hit on the backup QB.

“It always feels great getting after the quarterback, no matter where you’re coming from on the field,” Matthews said. “Just a good play. We did a good job disguising it. I think there was some miscommunication on their part as far as who to pick up. Kind of a layup, but I’ll take it. It’s been a while.”

Matthews had recorded 4 ½ sacks over a three-game span (Weeks 3-5) but had not had one since. His 5 ½ sacks on the season rank second on the team to Julius Peppers’ seven.

Overall, the Packers allowed the Cowboys to gain only 270 yards and held them to 1-for-11 on third downs. The frustrating part to Matthews was the two long runs surrendered – McFadden had a 45-yard run in the third quarter to go along with the early 50-yarder.

His second long run set up the Cowboys’ only score of the game, and those two runs accounted for more than one-third of Dallas’ total offense on the day.

“You can’t make those mistakes at this point in the season,” Matthews said. “Overall, I realize you can’t take those two plays away, but a pretty impressive performance by the defense.”

One catch, one score: Tight end Richard Rodgers only caught one pass, but it was good for a 3-yard touchdown, his seventh of the season.

That ties him with receiver James Jones for most on the team. Rodgers has five TD receptions in his last six games.

Click here for more Packers-Cowboys coverage