What's wrong with Adrian Peterson?

First, the caveats: I am not a running back, offensive lineman, coach, or even a waterboy, nor have I ever been. What follows are nothing more than observations from a somewhat informed and moderately intelligent (maybe) fan. But it doesn't take much intelligence to realize something has gone terribly wrong with the Vikings' running game for the past month and a half and that the Vikings' star running back has looked more like Adrian Murrell than Adrian Peterson over that span.

First, the numbers: In his first six games, AP accumulated 683 yards at 5.1 yards per carry. In his last six, he's managed just 485 yards and 3.9 per carry -- which doesn't sound too bad until you realize that 133 of those yards came in one game against Detroit (which actually has a surprisingly decent rushing defense this year). Take that one game out and AP has just 352 yards on 105 carries, a 3.4-yard average. That's a far cry from the 5.0 or so a carry we're used to seeing from him and has turned the Vikings into a badly one-dimensional team, which may have finally caught up with them in Arizona.

(Though I again doubt the "wisdom" that says Brett Favre had a bad game because the Cardinals were stopping the run and forcing him to pass a lot. If the Cards are playing eight in the box and stuffing the run, shouldn't that make it easier to pass? Again, the whole "good rushing game helps the passing game and vice versa" argument fails to pass the logic test. The lack of a running game may have forced the team into too many 3rd-and-longs, which would certainly have contributed to a poor passing performance, but that wouldn't explain how the team did on first and most second downs.)

Having watched the Vikings and their suddenly anemic running game over those six games, here are my (likely misguided) on what's wrong with the team and with Peterson himself:

The offensive line isn't opening up holes. Seems obvious enough, but why? How can a team with two road-graders at the tackle position and an all-world left guard suddenly not be able to block? Are John Sullivan and Anthony Herrera (or Artis Hicks) that bad?

I wouldn't say so, because no matter where the team is running, left, right, or center, the blocking is subpar. There's no push up the middle (When's the last time you say the Vikings' O-line move the line of scrimmage two or three yards downfield?) and outside runs are usually stopped before they can get started. Meanwhile, watch any big Chris Johnson run this year, and you'll see either a hole open up for him or a seal on the outside that allows him to turn the corner and run to daylight. Remember when we had an offensive line that could do that?

I don't know what the solution is, but this is one that's hard to pin on AP, at least. Or is it?

AP's slowing down. At least half a dozen times a game, it seems like AP gets just enough of a crease, starts striding downfield -- and then a tackler emerges from out of nowhere to get a piece of his leg or knock him down and he's limited to a three-yard gain. Again, maybe this is just my feeble observations or my expectation that he could do better, but these kind of plays seem to happen with frustrating regularity these days. If AP just had a little more juice or just could make a slight adjustment to his trajectory, he could avoid that tackler and rip off a big run. Clearly, at this stage of the season, every player is playing hurt, running backs especially, but maybe AP's got a little bit more of a hitch in his get-up than he'd like everyone to know and it's hurting his ability to make those sudden moves when he does have a hole to run through, however small. He's also getting caught from behind more times than I'd like to see. It's neat that he can run over William Gay, but is his physical running style costing him speed?

Cut the cutbacks. His TD run against the Lions notwithstanding, the cutback just hasn't been there for AP, but he keeps trying it anyway. It's a simple premise, really: If you stop running, the defense can catch up to you easier. I know that the line isn't opening up lanes for him to run through, but stopping and then trying to run in another direction where there isn't any room doesn't solve anything. I'd rather see AP run straight ahead into the line and hope that he can squirt through the other side or run over someone than cut back into another defender. And speaking of running straight ahead...

Stop running sideways. Going all the way back to the Steelers game, I was lamenting the stretch play every time it was run. The Vikings have stuck with it, though, to their detriment. It has all the potential of a pass to Naufahu Tahi, and usually can't even match the guaranteed three yards that play gets. In fact, I think this play has lost yardage more often than it's gained any. AP's lack of acceleration and the offensive line's inability to get out and throw blocks -- this isn't Matt Birk pulling from center any more -- have relegated his play to an automatic loss of down.

The next time the Tennessee Titans are on TV, watch how Chris Johnson runs and how his line blocks for him. It's amazing to see someone get that much open space, and I wonder how we can get back to that kind of rushing attack. I hope it happens over the next month or so, or else the Vikings will be in for yet another early preseason exit.