One man's prediction: San Diego 28, Vikings 17 The Chargers have quarterback Philip Rivers leading the league's top-ranked offense of 2010 and have upgraded a defense that also ranked No. 1 in the league with the addition of safety Bob Sanders and linebacker Takeo Spikes. The Vikings have the talent to surprise, but there are too many questions to pick them to win on the road against one of the AFC's best teams.

Record runner has challenge Four years ago as a rookie, Adrian Peterson caught a banged-up Chargers defense at precisely the right time. The result was an NFL-record 296 yards in a 35-17 victory. Four years later, Peterson is fresh off agreeing to a seven-year, $100 million contract, one that includes $36 million guaranteed, surpassing the $30 million in guarantees Titans RB Chris Johnson recently received. Peterson looked like his All-Pro self in the preseason, but the Chargers upgraded their defense with some speed and experience, including the run-stuffing Sanders.

Good Donovan, bad Donovan? So far, so good for Vikings QB Donovan McNabb. He has looked surprisingly comfortable in the new Vikings offense, which is built around the running game and high-percentage passing to the tight ends. But this offensive unit still hasn't played a full game together. And one of the primary weapons, TE Visanthe Shiancoe, missed the entire preseason because of a hamstring injury. The main question is whether Vikings have the McNabb who was really good for 11 years in Philly or the one that was really bad last year in Washington.

Can the Wall be replaced? The Williams Wall had to fall at some point. Pat, the nose tackle, is out of football. And Kevin, an All-Pro DT, is serving a two-game league suspension. Remi Ayodele will start at nose tackle and Letroy Guion will start at Kevin Williams' spot. The Vikings' new starter at left end, Brian Robison, needs to play well. If he doesn't, right end Jared Allen will get more attention and fewer chances to pressure Rivers. Putting pressure on Rivers is the key to beating the Chargers. The Vikings want to do it with their front four but might have to blitz more.


Vikings cornerback Antoine Winfield vs. San Diego wide receiver Vincent Jackson.

About Winfield He's not a shutdown corner, so he won't shadow Jackson. But all eyes will be on this matchup when the 6-5 Jackson lines up across from the 5-9 Winfield.

About Jackson At 6-5, 230 pounds, he's one of the league's bigger, more physical receivers. Had 2,265 yards and 16 TDs receiving in 2008-09 before holding out for all but five games last year.

Who has the edge? Jackson's size gives him advantages, but man coverage will be limited. Advantage: Jackson