Derrick Barnes and Marcus Davenport have officially been placed on IR. Barnes won't play for at least four weeks, while Davenport is expected to miss the rest of the season.

Defensive end Marcus Davenport and linebacker Derrick Barnes were both placed on IR Tuesday after suffering significant injuries in Detroit’s Week 3 triumph over the Arizona Cardinals. Davenport’s injury was reported as torn triceps, while Barnes suffered a knee injury.

The Detroit Lions placed two players on the injured reserve and signed wide receiver Tim Patrick to its 53-man roster on Tuesday. Patrick, who has played in the past two games for the Lions, is now officially on the roster after being elevated from the practice squad this season.