The Chicago Bears have put defensive tackle Christian Tupou (TOO'-poh) on the team's active roster.
The Bears also said Wednesday that they've put defensive tackle Nate Collins on injured reserve because of a knee injury.
The 6-foot-2, 290-pound Tupou played in all four of the Bears' preseason games. He had four tackles and one sack.
Collins has played in five games for the Bears this season and started twice. He had 12 tackles, one sack and one tackle for loss.