Niners, Chiefs, and... the Raiders? Week 4 Power Rankings Shake the Board

Four weeks in, and we've got four undefeateds—but only two look built for the distance. San Francisco sits atop the heap at 4-0 with a blistering 32.7 points per game, the kind of offensive firepower that separates contenders from pretenders. Kansas City checks in right behind at 29.5 PPG, because Andy Reid's offense…