Here's a look at the Vikings' players' fantasy potential heading into Week Eight's game against the Patriots:
Everything depends on Brett Favre. Period.
Favre's decision to play (let's not kid ourselves whose decision this has become) will have a huge effect on the offense. Assuming most fantasy owners have benched Favre for other options, it will most significantly impact Randy Moss, Percy Harvin and Visanthe Shiancoe.
I am going with the idea that RB Adrian Peterson will be a major factor either way. (It should be noted, though, that the Patriots shut down the Chargers' run game last week.)
Moss probably gets hurt the most if Favre sits. It's not that Tarvaris Jackson lacks arm strength; in reality, he has a very strong arm. But the coaches likely wouldn't dial up as many downfield passes with Jackson running the offense. And besides, Favre has a way of going against the coaches' wishes that, er, Jackson does not. Yet, anyway.
Harvin figures to be busy with either guy, but he might have different looks, depending on the QB. You might see Harvin more in the backfield with Jackson at QB, perhaps even taking direct snaps from center. The Vikings have been working on a package of Percy plays the past few weeks, and what better game to bust it out? But again, with Jackson, you'd have to assume they would throw the ball fewer times than with Favre unless they got in a big hole early.
Shiancoe is one of Favre's favorites, and they appeared to hook up for a TD catch last week. (Replays couldn't overturn the call despite everyone who was watching knowing it was a score.) It's hard to say what Jackson's effect might be. On the one hand, you could see Jackson leaning on a shorter-range receiver such as Shiancoe; on the other, there is no way he and Jackson could mimic the rapport that is there with Favre.
It's all up in the air until we hear what Favre's status is.