ORCHARD PARK, N.Y. (WIVB) -- Starting defensive backs Rasul Douglas and Taylor Rapp did not participate in Wednesday's walk-through practice due to injuries, Bills coach Sean McDermott said. Douglas hurt his knee when he collided with Rapp in the end zone while defending a touchdown catch by Rams receiver Cooper Kupp during Sunday's loss in Los Angeles. Rapp played in the game after being limited in practice and listed as questionable with neck and shoulder injuries sustained in Buffalo's win against San Francisco the week prior. Rookie receiver Keon Coleman, who has missed three games with a wrist injury, was a full participant Wednesday. Defensive end Casey Toohill (ribs) was limited. The Bills also have opened the practice window for defensive end Dawuane Smoot (wrist) and Baylon Spector (calf) to return from injured reserve. Buffalo (10-3) visits the Detroit Lions (12-1) on Sunday.