Pittsburgh quarterback Ben Roethlisberger was apparently knocked momentarily unconscious and left the team's game against Atlanta after being hit by three Falcons defenders while throwing a pass in the third quarter. Roethlisberger appeared to receive a helmet-to-helmet hit in the face mask from defensive end Chauncey Davis immediately after releasing the pass, which was dropped by Hines Ward with 7:40 left in the third. Defensive end Patrick Kerney and linebacker Edgerton Hartwell also hit the quarterback on the play. Roethlisberger was face down and motionless for several minutes before being rolled over onto his back by trainers.

Chad Brown, a Pro Bowl linebacker for Pittsburgh 10 years ago, was signed Thursday by the Steelers to add depth and experience at what suddenly has become a depleted position. The Super Bowl champions (1-3), losers of three in a row, added the 36-year-old Brown a day after Pro Bowl linebacker Joey Porter injured a hamstring during a routine indoor practice for Sunday's home game against Kansas City (2-2). Porter is listed as questionable.

Pittsburgh Steelers cornerback Ricardo Colclough will miss the rest of the season because of a neck injury. Colclough, a third-year player, was placed on the team's injured reserve list, the Steelers said Saturday. Rookie cornerback Anthony Madison was promoted to the active roster.