Rams vs. Vikings: Adrian Peterson is enormous test for an inexperienced Rams offense

The St. Louis Rams' defense has been the key to their success in 2012, but on Sunday they'll have to contend with the astonishing Adrian Peterson and the Minnesota Vikings--and no matter how successful you've been, that's an ordeal. How good has Adrian Peterson been this year? He gained 86 yards on the ground in his worst game of the season. He's averaged more than 10 yards per carry as may times as he's averaged fewer than four.

His 1600 yards through 13 games puts him within six yards of the season total of last year's leading rusher, Maurice Jones-Drew. In short: It's a good thing Michael Brockers, the Rams' rookie DT, has come on strong, because it's possible he'll never again face a running back as dangerous as Peterson is right now.

The Rams stifled two dangerous running backs last Sunday, when they held the Buffalo Bills' C.J. Spiller and Fred Jackson to 16 carries for 51 yards, but unlike Chan Gailey and company the Vikings know exactly what runs their offense, and won't give the Rams an assist by forcing Christian Ponder to throw the ball 50 times.

What's a great day against 2012 Adrian Peterson look like? 25 carries for 86 yards, a feat the 49ers managed in Week 3, before he'd gone from "pretty good for someone who was hurt" mode to "best running back ever" mode. In his last seven games, the best a team has done against him are the two times he's faced the Chicago Bears. On November he carried the ball just 18 times and only, as a result, gained 108 yards. Last week, during the Vikings' win, he took the ball 31 times and was held under five yards per carry for the first time in two months. Which is to say that he only gained 154 yards, and scored twice.