As the Vikings prepare for Sunday's game with the Raiders at Mall of America Field, we asked Vittorio Tafur, beat writer for the San Francisco Chronicle, to give us his up-close-and-personal scouting report on Oakland. Here are four things you need to know …

1) Darren McFadden will not play.The Raiders may not officially rule McFadden out until Sunday morning. But Tafur says there's almost no chance the sleek tailback will be cleared for action. "He's just getting out of his walking boot and starting to walk again," Tafur said. "He hasn't even started to run yet." That leaves Michael Bush as Oakland's workhorse and a pretty impressive contingency plan. Remember, Bush is coming off a career night in last week's 24-17 win in San Diego. On his way to 242 yards from scrimmage, he had a 55-yard reception, long runs of 44 and 30 yards and a 2-yard touchdown plunge in the first quarter. "He's a solid downhill runner who's proven difficult to tackle," Tafur said. "He's just very hard to bring down once he gets going. He's not your typical bruiser where he pounds through the line of scrimmage. He kind of tiptoes to the line. But once he gets past the line of scrimmage, you have to get a bunch of bodies on him. He's hard to bring down for linebackers and safeties." On top of that, Oakland's offensive line has been a pleasant surprise this season, opening holes for whichever back gets the call. 2) As quarterback Carson Palmer continues to clean away the rust in his game, a date with the Vikings will be like soaking in a bath of Lime-A-Way.Palmer arrived in Oakland on Oct. 19 via a trade with Cincinnati and was slow to get comfortable, throwing six interceptions in his first six quarters of work. But now he's starting to establish a rhythm, developing obvious chemistry with rookie receiver Denarius Moore. "When they first made the trade for Palmer, I thought it was nuts," Tafur said. "It sure seemed like they were giving up too much. But he's been a lot better than I thought he was going to be. And all their young receivers really like him, too. It's worked out well." The past two weeks, Palmer has found Moore nine times for 184 yards and two scores. Now, they get a date with the Vikings and a golden opportunity to attack a severely weakened secondary. 3) The Raiders defense remains susceptible, even with the Week 6 acquisition of Aaron Curry.Oakland ranks 26th in total defense, allowing 378.4 yards per game and is 25th against the run (132.4 ypg). Linebacker Rolando McClain has had a mediocre year and Quentin Groves has been, in Tafur's words, "pretty bad." Two weeks ago, in a 38-24 home loss to Denver, the Raiders surrendered 299 yards on the ground, an obvious indication of their defensive vulnerabilities. As for Curry? "He flies around a lot," Tafur said. "But he doesn't have great instincts. He won't always be in the right place or stay in his gap. Still, he's playing a lot better than Groves was. And he's a great athlete who at least has the ability to fly around and make plays." 4) Even with a checklist of obvious flaws, the Raiders are positioned to make the playoffs.Right now, they're all alone atop the AFC West and have three consecutive victories over the Chargers, an obvious boost of confidence. "They haven't just beaten San Diego, they've physically manhandled them," Tafur said. "I think they've found a way to expose the Chargers as kind of a soft team. So it's given the Raiders confidence. In the past, you'd always give the Chargers the upper-hand because of Philip Rivers. Now, Carson Palmer's playing well enough that that gap no longer exists." The Raiders face an encouraging situation. They're in first place by themselves in mid-November. But they're also only a game out of last place. "Still, It's their division to lose now," Tafur said.