1. Steve Smith
If you had just seen the end of the Panthers' 2009 season, you would have thought that Matt Moore to Steve Smith was one of the league's most feared QB to WR combinations. In the final 3.5 games of the season, Smith caught 19 passes for 378 yards and three touchdowns. He was on his way to having a big game against the Giants (5 receptions, 60 yards, one touchdown), before breaking his arm on the opening drive of the third quarter.
He has vowed his revenge against the Giants for breaking his arm, although he recently retracted those "immature" comments. Still, stopping Smith is key to stopping the Panthers' offense, revenge or no revenge.
2. Everette Brown
MLB Jon Beason is the unquestioned leader of the Panthers' defense. But over the last eight years, the Panthers' defensive player that worried offensive coordinators the most was Julius Peppers. Now, with Peppers a Chicago Bear, the Panthers will look to Everette Brown to fill a portion of the pass-rushing void left by Peppers' absence.
Brown is a relative unknown, having played sparingly in 2009, his rookie season. Despite being undersized, he has the ability to turn into a very good speed rusher. If the Giants successfully cancel out Brown, Eli Manning could have a while to spread the ball around to his talented receivers.
3. DeAngello Williams / Jonathan Stewart
It's kind of a cop out to pick two players here, but anyone who has seen a Panthers game over the past few years knows that their two-headed running back monster is the most dynamic duo in the league. Last year, the two combined for over 2,200 yards, with each runner piling up over 1,100 yards. Both could be feature backs for most teams, and the fact that their egos are small enough that they are willing to share carries only makes them more dangerous.
Both have been Giant-killers in the past (Stewart put up 206 yards in the Giants stadium finale), so it'll be key for the Giants to wrap up these two monsters on first contact.