Here's a matchup to watch in Sunday's Vikings-Chargers game:
Vikings RB Adrian Peterson vs. Chargers' run defense
The Vikings are in transition offensively, even if they feature a veteran QB and will do a lot of the same things as normal, as in giving the ball to Adrian Peterson 20-25 times a game in most weeks.
But the carries are more important in that the downfield passing game will not be as potent with WR Sidney Rice (and maybe Brett Favre) moving on. Donovan McNabb is an effective play-action passer and he has underrated arm strength. But his accuracy, especially on deep passes, is suspect.
So you can bet that the Chargers — especially their two great safeties, Bob Sanders and Eric Weddle — will be more concerned with the work of Peterson and are willing to trust their corners in coverage with less help outside.
They were the No. 4 run defense (93.8 yards allowed per game) last season, and though many of the faces return, there will be a change at coordinator with Greg Manusky replacing Ron Rivera. The principles of the 3-4 defense will be similar, and Manusky will rely on his quality inside linebackers, Takeo Spikes and Donald Butler (a first-time starter who can run and hit), to fill the gaps in the thick of things. Outside, there are health concerns with Shaun Phillips and Larry English, and though the preseason stats showed the team struggled against the run, expect this to be a tough assignment for the Vikings.
The offensive line is a work in progress, and OLT Charlie Johnson is one of the smaller in the league at his position. Chargers DRE Luis Castillo might give him fits.