The Cardinals have been headed the wrong direction for the past month, but there are two players the Green Bay Packers know could suddenly turn Arizona's fortunes around beginning Sunday at Lambeau Field.

Halfway through 2012, punt returner Patrick Peterson and receiver Larry Fitzgerald haven't come close to repeating their superb seasons of 2011, and their lack of explosive plays is one factor of many in the Cardinals' current four-game losing streak.

It's up to the Packers, who are pointed the other direction with three straight wins, to keep them quiet at least one more week. It could be the key to stretching Arizona's losing streak to five, but that's not a given, not with these two.

Peterson, a cornerback on defense, quickly made a name for himself as a rookie a year ago by tying a league record with four punt returns for touchdowns. Of all the players to accomplish that feat – the list includes Chicago's Devin Hester in 2007 – Peterson is the only one whose four return TDs were all 80 yards in length or better.

This year he has yet to break loose, however. Of his 30 punt returns thus far, his longest is 26 yards, the only one longer than 20. His 8.1-yard average this season is barely more than half of last year's 15.9 mark, which ranked second in the league behind Hester.

The Packers have watched as much, if not more, of Peterson's 2011 film than his 2012 tapes, and they aren't counting on the fact that his "sophomore slump" will last all season. Earlier this week, Mike McCarthy called Peterson the "starting point" for the scouting report against the Cardinals.

"All it takes is that one play," linebacker and special teamer Jamari Lattimore said. "The whole league isn't changing their opinion of him, just because he hasn't broken one or several. It doesn't mean it can't happen.

"He can make things happen any time in the game. You can be in the last second of the game, and he can make something happen. That's why you see snaps of him on their offense."

The more dangerous offensive player, though, is Fitzgerald, a sure Hall of Famer, who has set every major Cardinals franchise receiving record through his first eight seasons.

But his ninth year hasn't measured up, at least not yet. He's ranked eighth in the league with 45 receptions, but his 511 yards are just 18th because he hasn't made the big plays he's accustomed to making.

Fitzgerald's 37-yard TD catch against the Eagles in Week 3 is his only reception this season of at least 30 yards. His current average of 11.4 yards per catch is barely above his single-season career low of 11.3.

It's not just a quarterback issue, either, because even though Fitzgerald doesn't have Kurt Warner throwing to him anymore, he posted a 17.6-yard average last year (second in the league among players with at least 80 catches) with the same two QBs he has this year, Kevin Kolb and John Skelton.

He also has just a single 100-yard game this year compared to six a year ago.

All that said, the last thing the Packers will do is let their guard down against Fitzgerald. Players have said this week they've looked back at film from the 2009 NFC Wild Card game, when Fitzgerald physically outmuscled the Packers for two TD catches, making six grabs for 82 yards in all.

"He's a veteran receiver with crafty skills, so you can't really relax," said safety Morgan Burnett, who wasn't with the Packers yet in '09 but knows all about the game. "We've seen it on film where guys think they have him covered, and he's still able to catch the ball. You just have to trust your techniques and finish."

Another issue is the Packers' ups and downs this year against top-flight pass-catchers. Back in Week 2, with cornerback Tramon Williams leading the way, the Packers held Chicago's Brandon Marshall to just two catches for 24 yards. But in Weeks 4 and 5, New Orleans' Marques Colston (nine catches, 153 yards) and Indianapolis' Reggie Wayne (13-212) had huge games.

Those kinds of days are old hat to Fitzgerald, and the Packers must prevent Fitzgerald from returning to his old ways. Their own current streak may depend on it.

"He's capable of making a big play whether it's a deep pass or catching a screen and taking it 60, 70 yards," Burnett said. "You have to know where No. 11 is on the field."

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