The Vikings downed the Ravens in Baltimore 23-15 Saturday night in a preseason game.  Tarvaris Jackson threw for 82 yards on 7-11 passing with 1 touchdown and no interceptions.  Jackson left the game in the 2nd quarter with a knee injury.  He was replaced with Gus Frerotte.  Frerotte threw a 5-yard touchdown pass to Robert Ferguson.  Adrian Peterson touched the ball for the first time in a preseason game this season.  He had 8 carries for 30 yards and 1 catch for 22 yards.  The Vikings are 1-1 in the preseason and will host Pittsburgh next Saturday at 7pm, pregame on AM 1390-the Fan at 6pm.