Kansas City Chiefs quarterback Matt Cassel left Sunday's game in the fourth quarter with an undisclosed injury. Cassel, who has been under fire in Kansas City because of turnovers and inconsistent play, earlier fumbled away the ball at the Baltimore Ravens' 1-yard line and left the game with the Chiefs trailing 9-3 amidst boos and chants of "Brady, Brady." With Quinn at the helm, the Chiefs finished the drive with a field goal to trim the Ravens' lead to 9-6 with 5:44 to play in the game. The Chiefs opened the game with 10 Jamaal Charles running plays and just two pass plays. Charles had 20 carries in the first half.