Which came first: the Bernard or the Adrian?

Even before Bernard Berrian inked his huge deal with the Vikings, people were already picking Adrian Peterson to have a 2008 to put his rookie year to shame. The excitement reached a fever pitch after Berrian was signed, as people believed he would open a passing game that was largely ineffective in Peterson's rookie year. With Berrian and an improved passing game in 2008, Peterson won't face eight defenders in the box and will run wild through opposing defenses all year long; 2,000 yards is a distinct possibility. If you play fantasy football and wind up with the fourth pick or lower -- or in some drafts, the second pick -- you likely won't even sniff Peterson.

But here's the thing: If Peterson is going to have such a phenomenal year because of the improved passing game, how will the passing game actually be improved if Peterson is rushing for 2,000 yards? An offense can only run so many plays, and if the bulk of them are going to Peterson (and maybe Chester Taylor), that won't leave much for Bernard Berrian and company. Going back again to fantasy drafts, I've heard two reasons why a player, especially a running back, might be poised for a breakout year:

Situation A: The team has a good passing game.
"That'll open up lots of holes for him! He'll have a huge year!"

Situation B: The team has a poor passing game.
"He's all they've got! He'll get tons of carries and have a huge year!"

Well, they can't both be true, can they? So, which is it? How does having a good passing game impact the running game (and vice versa)?

On the surface, it seems to make sense. But if you think about it, does one beget the other? Consider these questions:

Q: How do you have a good running game?
A: Have a good passing game to open holes for the running back.

Q: How do you have a good passing game?
A: Have a good running game so your receivers are single covered.

Er...OK. Chicken, meet egg.

Nobody would dispute that it's easier to run against seven in the box than it is against eight (or, in some cases against the Vikings last year, nine). But if the defense is stacking up to stop the run, shouldn't that mean the pass is wide open? But why are they stacking up to stop the run? Probably because the running game is very good, clearly better than the passing game. And if you're an offensive coordinator, shouldn't you be using what works? Do good running teams abandon or minimize the run just because the defense tries really hard to stop it. Of course not.

But when the offense does pass (or run against a team defending primarily against the pass), they should meet with some success, better than would be normally expected, right? They'll probably still pass fairly infrequently, but the results should be pretty good.

So maybe that's the key. A team that accumulates a lot of rushing yards should pass relatively infrequently but should be rather successful when they do pass. And a team that racks up the passing yardage runs infrequently but should be successful when they do run. In other words, high accumulation (raw yardage) in one stat should lead to a high rate (yards per carry or pass) in the other.

That's the theory, at least. This post is long enough, so I'll run the numbers and see what I come up with sometime this weekend. For now, just think about it and realize that if Bernard Berrian does somehow rack up 1,160 yards, it'll be more likely to come on 60 catches than on 80.