PONTIAC, Mich. (AP) _ Detroit Lions left tackle was knocked out of Sunday's game against Atlanta with a bruised right shoulder late in the first quarter.

It was not clear when the injury occurred, because Gibson jogged off the field after a false-start penalty. The second-year player, who has started every game this season, was replaced by Barrett Brooks.

Gibson missed all of last year after having surgery on his left shoulder. Detroit drafted the 6-foot-4, 380-pounder out of Wisconsin with the 27th overall pick in the 1999 draft.