Bears-Vikings preview: Vikings ball

Early on, the Bears’ defense was annihilated twice a year by Adrian Peterson when the All-World running back came into the NFL in 2007. Peterson rushed for more than 120 yards in three of his first go’s against the Lovie Smith defense.

Since 1008, however, Peterson has failed to average 4 yards per carry in any of the four meetings with the Bears, with a high of 94 yards and an average of 67 per game against the Bears.

With all of that success, Peterson is still what causes lost sleep on the Chicago defense.

“He is elite,” said defensive coordinator Rod Marinelli. “He hits that cut and he’s downhill, violently. And then he’s got that second and third cut in the open field. Then he goes. He’s such a great competitor.”

Receiver/returner Percy Harvin’s status and threat is unclear because of an ankle injury. But the AP issues are far greater.

Peterson is of particular note Sunday for two reasons:

1. He has returned from a catastrophic knee injury to lead the league in rushing. In a league committed to passing and points, Peterson through 10 games has 1,128 yards, a 5.8-yard average per carry and seven touchdowns.

By comparison, the NFL’s leading yardage receiver, Detroit’s Calvin Johnson, had 1,117 yards and three touchdowns through 10 games.

2. The Bears’ avowed objective each week is to turn a team one-dimensional by taking away the opposing running game. But since ranking No. 1 with an NFL-best 77.9 yards allowed per game after the Carolina game, the Bears have given up an average of nearly 136 rushing yards per game. The result is a decline to No. 8 and giving up 92.

They have been found wanting against top backs -- 100-yard games to Chris Johnson in Tennessee, Arian Foster of Houston, and the San Francisco 49ers with Frank Gore and Kendall Hunter combining for 105 -- and no back is more “top” than Peterson.

Peterson had one 100-yard game in his first six outings. He has rushed for 153, 123, 182 and 171 in the last four. Meaning: He is getting stronger. He admits he did not feel himself earlier in the year, but now...

“Each week I’ve felt myself going through this transition of getting stronger and just really getting out there into some live football,” Peterson said. “There’s no way to duplicate that.

“I’m 100 percent. But with that being said, there’s another level that I’m trying to reach after 100 percent. I feel like I’ve been better than I was last year. The past couple of weekends, I feel even stronger. That’s what I’m excited about the most.”

The Bears have played with a safety up in run support frequently over the past several games, with only limited success. But their base scheme has generally succeeded against the Vikings because it does not over-pursue or leave itself vulnerable to cutbacks, a Peterson strength.

The concern now, however, is that Foster had 85 yards in the first half of the Houston game with the zone-blocking/cutback scheme, and the San Francisco 49ers obliterated the edges of the defense with jumbo packages and “wham” blocking from fullbacks and tight ends.

“Anytime we come off a game and something hurts us, we go in, install it, re-fit it,” Marinelli said. “Because we’ll see it again down the line, somewhere, sometime, this week, next week. We’ll see some of that stuff again.

“We see the corrections we can make. We go through it, re-teach it, fit it up and then we’ve got to go play fast with it. Beat blocks, get off blocks, all those basic things.”

If the Bears indeed can continue their mastery over Peterson, the Vikings become the hunted. Quarterback Christian Ponder was knocked out of the second Bears game last year with a hip injury and has been wildly inconsistent through significant portions of this season.

Ponder started the season with completion percentages of 60 percent or better in the Vikings’ first six games. Minnesota won four of those. Then came three straight with sub-55 percentages and passer ratings in the 30’s in two of the three. Then he put away the Detroit Lions with 24-of-32 passing in his last outing.

A defensive key will be pressuring Ponder on third downs where he ranks 27th in the NFL with a rating of 69.6.

That means Julius Peppers in Ponder’s eye and mind, which will be easier said than done if he lines up over rookie left tackle Matt Kalil.

Kalil has allowed just one sack and two hits all season, according to ProFootballFocus.com.