McFadden hauled down four passes for 28 yards and Marcel Reece scored the only touchdown for the Raiders (1-1), who notched their first victory following an season-opening loss to Indianapolis.
Terrelle Pryor went 15-of-24 through the air for 126 yards for the Raiders, limited the Jaguars to just 248 yards of total offense.
Jacksonville running back Maurice Jones-Drew sustained an ankle injury and was held out of the second half.
Florida bear attack: Black bear mauls woman's face
Ron Burgundy interviews Peyton Manning on SportsCenter