The San Francisco 49ers may be facing their toughest matchup of the season when they take on the Green Bay Packers at Lambeau Field to open up their season. Aaron Rodgers leads that offense as well as any quarterback in the league - he's right up there with Drew Brees and Tom Brady. But there are some issues with the team, namely on defense.

They've got a defense that makes big plays with regularity, but allows them almost the same amount of time. In 2011, they were the kind of defense that gave up a ton of big yardage before picking off a football in the end zone, which sounds great, but when they weren't able to pick that ball off, they gave up points.

And that kind of football game certainly favors the 49ers. More importantly, that kind of football game is excellent for morale at certain positions if you happen to come out on the winning end. One group that can certainly benefit from Green Bay's secondary is the group of receivers in San Francisco.

There's some new faces in Randy Moss, Mario Manningham and A.J. Jenkins, and a familiar face or two that could really use a great game right out of the gate, like Michael Crabtree and Kyle Williams. Every one of these players has his reasons for needing a big game. Let's look at them, shall we?

• Randy Moss needs a big game because he's at the end of his career. He's lost his desire to play time and time again, giving up right there on the football field. Chaos in the Green Bay secondary could be the difference between him lasting all season and lasting three weeks.
• Mario Manningham needs a big game because he was probably expecting to come into San Francisco as the top dog. That hasn't happened yet, and that could be demoralizing for him. He needs to get out there and make some catches and know that he belongs with the 49ers.
• Michael Crabtree needs a big game because he's never really been "that guy" in San Francisco. He's always come up short of expectations and he's always had terrible performances near the beginning of the season. Coming out of the gate with the affirmation that he is the No. 1 receiver on this team would be great for him.
• Kyle Williams needs a big game because there's no faith in him anymore. Even if you don't hear about it, every time he takes the field, fans think back to the NFC Championship game, however unfairly. Coming out and catching a ball or two and perhaps fielding a couple kicks would be huge.
• A.J. Jenkins needs a big game because the expectations for him are so low. Nothing is as good for a rookie as feeling like the NFL game clicks. It doesn't need to be a huge game, but a touchdown reception past a Packers defensive back would be huge for him.

So that's why all the 49ers receivers need a big game. Against the Green Bay secondary, it's certainly a possibility. There's a few things set in their secondary: Tramon Williams is the top guy and will either be matched up with Crabtree, Manningham or Moss, Charles Woodson will be playing safety for a large portion of the game, and Morgan Burnett is always a solid starter.

Aside from that, there's not really ... another starting cornerback. There's Jarrett Bush, Jerron McMillian and Sam Shields, not to mention Davon House. None of those players have really made a name for themselves, and whoever Williams isn't covering might just be poised for a big day. They're still a ball-hawking defense, and Alex Smith will surely be put on his back once or twice, but if the 49ers receivers don't have a big day, the game probably didn't go well for San Francisco.

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